With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin...With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.展开更多
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka...The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.展开更多
Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practica...Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.展开更多
Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious ...Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious metal ions,V_(2)O_(3)spiny hollow nanospheres(pV_(2)O_(3)SHN),was synthe sized through a one-step hydrothermal-as sis ted methodology for the adsorption of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) from the leaching solution of electronic waste.The results reveal that the p-V2O3SHN hierarchy was successfully constructed with a hollow structure and dense spiny morphology.The prepared p-V2O3SHN can effectively remove precious metal ions such as Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ),with the selective capture order being Au(Ⅲ)> Ag(Ⅰ)> Pt(Ⅳ)> Pd(Ⅱ)> other metal ions.This superior adsorption capability can be attributed to the multi-diffusible,intermingled composition,and numerous active sites decorating the p-V2O3SHN hierarchy,facilitating the uptake of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) ions from electronic waste.The Langmuir model provided a better fit for the uptake process,revealing maximum uptake capacities of 833.33 mg/g for Au(Ⅲ),370.37 mg/g for Ag(Ⅰ),42.01 mg/g for Pd(Ⅱ),and 77.51 mg/g for Pt(Ⅳ) on p-V_(2)O_(3)SHN.Remarkably,p-V_(2)O_(3)SHN exhibited a robust affinity for the adsorbate due to the presence of surface defects and reduction reactions.The new p-V2O3SHN also demonstrated good reusability for three sorption cycles,highlighting its potential for electronic waste treatment.Due to its facile synthesis and excellent efficiency,hierarchical p-V2O3SHN presents itself as a promising candidate for the selective uptake of Au(Ⅲ),Ag(Ⅰ),Pt(Ⅳ),and Pd(Ⅱ) from electronic waste.展开更多
Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report...Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report to embed the CeO_(2)nanospheres into the organic polymer network using electrostatic spinning technology to prepare polyvinyl alcohol(PVA)-encapsulated CeO_(2)nanospheres composite nanofibrous membranes(PVA-CeO_(2)) for the first time,which is beneficial to improving the dispersion and biocompatibility of CeO_(2)nanosphere without altering the original antioxidant properties of CeO_(2).Detailed characterization of the as-prepared composite nanofibrous membranes reveals that CeO_(2)was successfully introduced into the PVA fibers with strong interactions,thus enhancing the thermal stability and fracture toughness of the nanoifbers.As a result,PVA-CeO_(2)exhibits superior UV shielding performance,antioxidant performance and bacteriostatic performance.Meaningfully,PVA-CeO_(2)has strong absorbance in both UVA and UVB bands when the CeO_(2)concentration in the nanoifber membrane reaches 1.5 wt%,and shows an excellent scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl(DPPH)radicals with a scavenging rate of 86.52%.Moreover,the Kirby-Bauer(K-B) method of agar diffusion test further confirms that PVA-CeO_(2)has antimicrobial ability against three types of representative strains,including Gram-positive bacteria(Staphylococcus aureus),Gram-negative bacteria(Escherichia coli) and fungi(Candida albicans).Importantly,no obvious cytotoxicity is observed for PVA-CeO_(2)even though the amount of embedded CeO_(2)nanosphere reaches as high as 1.5 wt%.This study reveals new avenues for improving the future smart design of CeO_(2)-based nanoifber membrane composite materials for biological antioxidants.展开更多
Listeria monocytogenes(LM)is a dangerous foodborne pathogen for humans.One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone(3H2B)gas.In this study,the synthesis of 3-(...Listeria monocytogenes(LM)is a dangerous foodborne pathogen for humans.One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone(3H2B)gas.In this study,the synthesis of 3-(2-aminoethylamino)propyltrimethoxysilane(AAPTMS)functionalized hierarchical hollow TiO_(2)nanospheres was achieved via precise controlling of solvothermal reaction temperature and post-grafting route.The sensors based on as-prepared materials exhibited excellent sensitivity(480 Hz@50 ppm),low detection limit(100 ppb),and outstanding selectivity.Moreover,the evaluation of LM with high sensitivity and specificity was achieved using the sensors.Such stable three-dimensional spheres,whose distinctive hierarchical and hollow nanostructure simultaneously improved both sensitivity and response/recovery speed dramatically,were spontaneously assembled by nanosheets.Meanwhile,the moderate loadings of AAPTMS significantly improved the selectivity of sensors.Then,the gas-sensing mechanism was explored by utilizing thermodynamic investigation,Gaussian 16 software,and in situ diffuse reflectance infrared transform spectroscopy,illustrating the weak chemisorption between the-NHgroup and 3H2B molecules.These portable sensors are promising for real-time assessment of LM at room temperature,which will make a magnificent contribution to food safety.展开更多
In this study, hydrothermal carbon nanospheres(HCNs) were prepared by hydrothermal carbonization using glucose as the precursor, and introduced to improve the properties of water-based drilling fluid for the first tim...In this study, hydrothermal carbon nanospheres(HCNs) were prepared by hydrothermal carbonization using glucose as the precursor, and introduced to improve the properties of water-based drilling fluid for the first time. The variation in rheological and filtration characteristics of water-based drilling fluid with varying concentrations of HCNs were compared between the cases before and after thermal aging. The results demonstrated that HCNs had little influence on the rheological properties of bentonite base mud,but could effectively reduce its filtration loss after thermal aging at 220℃ For polymer-based drilling fluid, HCNs also exhibited minor influence on the rheology. The H-B model was the best fitting model for the rheological curves before thermal aging. After hot rolling at 220℃,the viscosity retention rate increased from 29% to 63%-90% with addition of HCNs, and the filtration loss decreased by 78% with 1.0w/v% HCNs. Meanwhile, the polymer-based drilling fluid with 0.5 w/v% HCNs maintained relatively stable rheology and low filtration loss after statically thermal aging at 200℃ for 96 h. For a bentonitefree water-based drilling fluid prepared mainly with modified natural polymers, the viscosity retention increased from 21% to 74% after hot rolling at 150℃ with 0.5 w/v% HCNs, and was further improved when HCNs and potassium formate were used in combination. The mechanism study revealed that,HCNs could trap dissolved oxygen, scavenge the free radicals and cross link with polymers, which prevented thermal oxidative degradation of polymers and improved the thermal stability of water-based drilling fluid. Meanwhile, HCNs could inhibit clay hydration and swelling in synergy with partially hydrolyzed polyacrylamide by physically sealing the micropores, contributing to shale formation stability.Furthermore, HCNs could effectively improve the lubrication and anti-wear performance of drilling fluid.This study indicated that HCNs could act as green, sustainable, and versatile additives in water-based drilling fluid.展开更多
Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodete...Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.展开更多
Amorphous transition metal compounds(a-TMC)become one of the most promising pre-catalysts toward oxygen evolution reaction(OER)due to their high-entropy nature and flexible self-reconstruction to highly active derivat...Amorphous transition metal compounds(a-TMC)become one of the most promising pre-catalysts toward oxygen evolution reaction(OER)due to their high-entropy nature and flexible self-reconstruction to highly active derivatives.However,the loosen bonds inside the amorphous structure make it an electronic insulator with unstable structure.Here,monodispersed Ni^(2+)-phytate nanospheres implanted by Fe^(3+)ions(NS_(FeNiPA))were firstly prepared and subsequently transferred into homogeneous high-entropy type Fe-Ni-P-O-C amorphous nanospheres(CNS_(FeNiPO)).It is shown that the CNS_(FeNiPO) presents robust structure and remarkable Fe ions migration during potential-driven activation process,which benefits efficient surface reconstruction and spherical morphology preservation.The CNS_(FeNiPO) with low mass loading of 0.1mg/cm^(2)could deliver small overpotential of 270mV at 10mAcm^(−2)and almost 100%retention of the initial current density after 10h test.The improved electrocatalytic activity is attributed to the boosted electron transfer from Ni sites to O-containing intermediates by introduction of Fe and P atoms.Moreover,rechargeable Zn-air battery with CNS_(FeNiPO)+Pt/C could achieve lower charge potential platform and better cycling performance than that with commercial RuO_(2)+Pt/C.This work provides new insights into the design and understanding of high-entropy amorphous pre-catalysts toward OER.展开更多
The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported mu...The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported multiple transition metal sulfides(NiWCoS/NC)electrocatalysts were prepared by combining the radiation oxidation synthesis and synchronous carbonization-sulfurization.Initially,the precursor material(NiWCoS/OANI,here OANI refers to oligoaniline)containing sulfurand multiple transition metal(Ni,W,and Co)ions loaded on oligoaniline nanospheres was directly one-pot synthesized at room temperature under γ-ray radiation.Subsequently,NiWCoS/NC electrocatalysts were successfully prepared by calcining the NiWCoS/OANI precursor at 800℃.The electrocatalytic performance of NiWCoS/NC for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)was characterized by electrochemical analysis methods including linear sweep voltammetry,cyclic voltammetry,chronoamperometry,and electrochemical impedance spectroscopy.The influence of the relative content of the loaded transition metals on the electrocatalytic performance was also investigated.The results indicate that the novel NiWCoS/NC electrocatalyst can significantly reduce the overpotential and Tafel slope for both HER and OER compared to corresponding electrocatalysts with single metal or metal sulfide component.When NiWCoS/NC with a molar ratio of 3:6:10 for W,Co,and S elements was used as electrode material,the overpotentials for HER in 0.5 mol/L H_(2)SO_(4) and OER in 1 mol/L KOH are only 161 mV and 243 mV at a current density of 10 mA/cm^(2),respectively.The Tafel slopes are 74 mV/dec and 88 mV/dec,respectively.The work provides a new direction and method for the design and green facile preparation of high-efficiency overall water splitting catalysts.展开更多
The two-dimensional(2D)layered material molybdenum disulfide(MoS_(2))exhibits a special Mo-S-Mo sandwich structure with a rather large spacing,making it a promising candidate as an anode material for sodium storage ap...The two-dimensional(2D)layered material molybdenum disulfide(MoS_(2))exhibits a special Mo-S-Mo sandwich structure with a rather large spacing,making it a promising candidate as an anode material for sodium storage applications.Unfortunately,the practical applications are limited by their intrinsically low electrical conductivity,significant volume alteration and severe particle agglomeration.In this study,we designed a new two-step solvothermal strategy to synthesize ultrathin nanosheetassembled MoS_(2)hollow nanospheres strongly located onlignite-based carbon(MoS_(2)/C)without any template.The ultrathin nanosheets assembled into hollow structures mitigated the volume changes of MoS_(2)during the(dis)-charge cycles,facilitated Na+diffusion,and reduced the migration energy barrier within MoS_(2).Lignite-based C enhances the electrical conductivity of MoS_(2),prevents its aggregation,and alleviates mechanical stress during repeated(dis)charging.The resultant hollow spherical MoS_(2)/C composite exhibits outstanding cyclability and rate performance when used as an anode in sodium-ion batteries,as it delivers a high specific capacity of 515.8 mAh g^(-1)after 1000 cycles at 1.0 A g^(-1),with a 94.34%capacity retention rate.Even at a high current density of 20 Ag^(-1),a capacity of 431 mAh g^(-1)can still be obtained after 2000cycles.In particular,the initial Coulombic efficiency of the MoS_(2)anode is markedly enhanced by the incorporation of lignite-based C.展开更多
The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon ...The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.展开更多
Activating both metal and lattice oxygen sites for efficient oxygen evolution reactions(OER)is a critical challenge.This study pioneers a novel approach,employing cobalt-nickel glycerate solid spheres(CoNi-G SSs)as se...Activating both metal and lattice oxygen sites for efficient oxygen evolution reactions(OER)is a critical challenge.This study pioneers a novel approach,employing cobalt-nickel glycerate solid spheres(CoNi-G SSs)as self-sacrificial templates to synthesize yolk-shell structured CoNi-G SSs@ZIF-67 nanospheres.The derived NiCo2S4@CoS2/MoS2 double-shelled hollow nanospheres integrate the adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM),enabling synergistic dual catalytic pathways.Nickel modulation facilitates active species reconstruction in NiCo_(2)S_(4),enhancing lattice oxygen activity and optimizing the LOM pathway.Characterization results indicate that anode activation triggered the redox processes of metal and lattice oxygen sites,involving the formation and re-filling of oxygen vacancies.Additionally,the CoS_(2)/MoS_(2) heterostructure enhances the AEM pathway,as supported by density functional theory calculations,which demonstrate optimized adsorption of intermediates for both hydrogen evolution reaction and OER.The assembled anion exchange membrane water splitting device can deliver a catalytic current of 500 mA cm^(-2) at 1.74 V under commercial catalytic operating conditions(1 mol L^(-1) KOH)for 150 h,with negligible degradation.This work provides important insights into the understanding of OER mechanisms and the design of high-performance water-splitting electrocatalysts,while also opening new avenues for developing multifunctional materials with multi-shell structures.展开更多
Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrins...Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrinsic electronic structure with d-orbitals fully filled, thus limiting the activation and reduction of CO_(2). To address this issue and maximize the photoreduction of CO_(2), herein we have designed Au@CZS@MO-400 triple-shelled hollow nanospheres by depositing Cd_(0.7)Zn_(0.3)S (CZS) on the outer surface of the MO-400 (MnO_(2) annealed at 400 ℃) hollow nanospheres and then Au nanoparticles on the CZS surface. It is manifested that the resultant 3%Au@CZS@MO-400 achieves a remarkably boosted photoreduction of CO_(2) with the CO/CH_(4) yield rates as high as 68.25/12.42 µmol g^(-1) h^(-1), increased by 3.7/1.5 times over MO-400 and 12.9/1.5 times over CZS. The combined analyses from X-ray photoelectron spectroscopy and density functional theory calculations confirm the creation of electron-deficient Auδ+ active sites by modulating their electron configuration by CZS, consequently decreasing the CO_(2)-Au antibonding-orbital occupancy to reinforce the adsorption strength of CO_(2) onto the Au active sites and in turn boost the photoreduction of CO_(2). Moreover, it is demonstrated that the Au@CZS@MO-400 hollow nanospheres are quite efficient for supplying the Au cocatalyst with photoelectrons for CO_(2) reduction reactions due to the good energy band matching, unique hollow structure and high electron spin polarization of MO-400. This work provides important guidance for understanding and modifying photocatalysts to maximize their photoreduction of CO_(2).展开更多
The distribution of ￣(3)H-mitoxantrone polybutyl cyanoacrylate nanospheres(￣(3)H-DHAQ-PBCA-NS)in the viscera,muscle and tumors of human hepatocellular carcinoma (HCC)model in nude mice was studied with liquid scinti...The distribution of ￣(3)H-mitoxantrone polybutyl cyanoacrylate nanospheres(￣(3)H-DHAQ-PBCA-NS)in the viscera,muscle and tumors of human hepatocellular carcinoma (HCC)model in nude mice was studied with liquid scintillation counting techniique. The results showed that the ￣(3)H-DHAQ-PBCA-NS had remarkable liver targeting effect. The content of ￣(3)H-DHAQ-PBCA-NSin liver and heterotopic liver tumor was found to be 71.31±10. 49% of total amount of drug in animal body. It was also found that the content of ￣(3)H-DHAQ-PBCA-NS in liver was higher than that in liver tissue, and the content of ￣(3)H-DHAQ-PBCA-NS in annpit tumor was higher than that in armpit muscle tissue,but had no significant difference;It provides an ideal preparation for the DHAQ admini-stration.展开更多
Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion k...Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)).展开更多
Objective:To study the biocompatibility and neovascularization of the PLGA nanospheres wrapped with vascular endothelial growth factor(VEGF).which can improve bladder acellular matrix graft(BAMG) with local continuous...Objective:To study the biocompatibility and neovascularization of the PLGA nanospheres wrapped with vascular endothelial growth factor(VEGF).which can improve bladder acellular matrix graft(BAMG) with local continuous release of VEGF.Methods:A total of 18 rabbit model (length of stenosis:3cm) with anterior urethral stricture were used as experimental animals and divided into three groups.Group A as the control group:Simple BAMG scaffold materials for urethral reconstruction.Group B as the blank group:PLGA microspheres modified BAMG for urethral reconstruction.Group C:PLGA conjugated with VEGF and modified BAMG for the urethral reconstruction.All rabbits underwent urethral angiography after 7 days,15 days,1 month and 3 months after the operation,and one rabbit in each group was sacrificed to be prepared for the organization histologic examination,HE staining,masson staining,CD31,34 and a-SAM immunohistochemical detection in the repaired sites.Results:In group A,significant urethral restenosis occurred in two rabbits after 15 days of the operation,HE and masson staining showed a lot of collagen arranged in the repaired sites,and there were a large number of inflammatory cell infiltration,and there were also CD31,34 in the repaired sites.a-SAM microvascular tag count showed a small amount of microvascular;Croup B showed anastomotic restenosis,HE and masoon staining showed inflammatory cell infiltration and collagen deposition;Group C:urethrography showed lumen patency.There were a small amount of inflammatory cell infiltration after 7 and 15 days after the operation,and there were also CD31,34 in the repaired sites.The a-SAM microvascular tag count showed many microvascular.And the difference was significant.Conclusions:Anterior urethral reconstruction with sustained-release of VEGF by PLGA nanospheres modified BAMG stents can reduce postoperative restenosis.It can also reduce collagen deposition and scar formation,promote angiogenesis of the repair tissue;therefore it in valuable in the tissue-engineered urethral reconstruction.展开更多
In this work,a novel vacuum-assisted strategy is proposed to homogenously form Metal-organic frameworks within hollow mesoporous carbon nanospheres(HMCSs)via a solid-state reaction.The method is applied to synthesize ...In this work,a novel vacuum-assisted strategy is proposed to homogenously form Metal-organic frameworks within hollow mesoporous carbon nanospheres(HMCSs)via a solid-state reaction.The method is applied to synthesize an ultrafine CoSe2 nanocrystal@N-doped carbon matrix confined within HMCSs(denoted as CoSe2@NC/HMCS)for use as advanced anodes in highperformance potassium-ion batteries(KIBs).The approach involves a solvent-free thermal treatment to form a Co-based zeolitic imidazolate framework(ZIF-67)within the HMCS templates under vacuum conditions and the subsequent selenization.Thermal treatment under vacuum facilitates the infiltration of the cobalt precursor and organic linker into the HMCS and simultaneously transforms them into stable ZIF-67 particles without any solvents.During the subsequent selenization process,the“dual confinement system”,composed of both the N-doped carbon matrix derived from the organic linker and the small-sized pores of HMCS,can effectively suppress the overgrowth of CoSe2 nanocrystals.Thus,the resulting uniquely structured composite exhibits a stable cycling performance(442 mAh g^−1 at 0.1 A g^−1 after 120 cycles)and excellent rate capability(263 mAh g^−1 at 2.0 A g^−1)as the anode material for KIBs.展开更多
Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-...Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-Sb-Cu nanoparticles have a specific hollow structure with a uniform particle size of 10-20 nm.As there are not any hard templates in the synthesis system,a galvanic displacement reaction mechanism is proposed to account for the formation of the hollow nanostructures.When the alloy powders are used as anode materials for lithium-ion batteries,they exhibit relatively high electrochemical capacity and good cyclic retention.The good electrochemical performance can be attributed to the inactive Cu species.During electrochemical reactions,the inactive copper phase in the hollow structure serves as a soft and ductile matrix,which alleviates the mechanical stresses caused by the severe volume change during lithium insertion and extraction.With their high reversible capacities,the Sn-Sb-Cu alloys are a promising candidate as the anode material of rechargeable lithium-ion batteries.展开更多
In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which c...In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.展开更多
基金supported by Natural Science and Engineering Research Council of Canada(RGPIN-2017-06737)Canada Research Chairs program,the National Key Research and Development Program of China(2017YFD0601005,2022YFD0904201)+1 种基金the National Natural Science Foundation of China(51203075)the China Scholarship Council(Grant No.CSC202208320361).
文摘With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.
基金financially supported by the project of the National Natural Science Foundation of China(52322203)the Key Research and Development Program of Shaanxi Province(2024GHZDXM-21)。
文摘The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2020R1C1C1003375)。
文摘Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.
基金supported by the Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(No.ES202306).
文摘Treatment of precious metals in electronic waste has attracted tremendous attention and is essential for both environmental protection and resource sustainable development.In this study,a novel adsorbent for precious metal ions,V_(2)O_(3)spiny hollow nanospheres(pV_(2)O_(3)SHN),was synthe sized through a one-step hydrothermal-as sis ted methodology for the adsorption of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) from the leaching solution of electronic waste.The results reveal that the p-V2O3SHN hierarchy was successfully constructed with a hollow structure and dense spiny morphology.The prepared p-V2O3SHN can effectively remove precious metal ions such as Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ),with the selective capture order being Au(Ⅲ)> Ag(Ⅰ)> Pt(Ⅳ)> Pd(Ⅱ)> other metal ions.This superior adsorption capability can be attributed to the multi-diffusible,intermingled composition,and numerous active sites decorating the p-V2O3SHN hierarchy,facilitating the uptake of Au(Ⅲ),Ag(Ⅰ),Pd(Ⅱ),and Pt(Ⅳ) ions from electronic waste.The Langmuir model provided a better fit for the uptake process,revealing maximum uptake capacities of 833.33 mg/g for Au(Ⅲ),370.37 mg/g for Ag(Ⅰ),42.01 mg/g for Pd(Ⅱ),and 77.51 mg/g for Pt(Ⅳ) on p-V_(2)O_(3)SHN.Remarkably,p-V_(2)O_(3)SHN exhibited a robust affinity for the adsorbate due to the presence of surface defects and reduction reactions.The new p-V2O3SHN also demonstrated good reusability for three sorption cycles,highlighting its potential for electronic waste treatment.Due to its facile synthesis and excellent efficiency,hierarchical p-V2O3SHN presents itself as a promising candidate for the selective uptake of Au(Ⅲ),Ag(Ⅰ),Pt(Ⅳ),and Pd(Ⅱ) from electronic waste.
基金Project supported by the National Natural Science Foundation of China (22301012)the R&D Program of Beijing Municipal Education Commission (KM202310011005)。
文摘Cerium oxide(CeO_(2)) has attracted much attention in recent years owing to its reversible switch ability in Ce^(3+)/Ce^(4+)redox to produce improved antioxidation properties for biomedical applications.Here,we report to embed the CeO_(2)nanospheres into the organic polymer network using electrostatic spinning technology to prepare polyvinyl alcohol(PVA)-encapsulated CeO_(2)nanospheres composite nanofibrous membranes(PVA-CeO_(2)) for the first time,which is beneficial to improving the dispersion and biocompatibility of CeO_(2)nanosphere without altering the original antioxidant properties of CeO_(2).Detailed characterization of the as-prepared composite nanofibrous membranes reveals that CeO_(2)was successfully introduced into the PVA fibers with strong interactions,thus enhancing the thermal stability and fracture toughness of the nanoifbers.As a result,PVA-CeO_(2)exhibits superior UV shielding performance,antioxidant performance and bacteriostatic performance.Meaningfully,PVA-CeO_(2)has strong absorbance in both UVA and UVB bands when the CeO_(2)concentration in the nanoifber membrane reaches 1.5 wt%,and shows an excellent scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl(DPPH)radicals with a scavenging rate of 86.52%.Moreover,the Kirby-Bauer(K-B) method of agar diffusion test further confirms that PVA-CeO_(2)has antimicrobial ability against three types of representative strains,including Gram-positive bacteria(Staphylococcus aureus),Gram-negative bacteria(Escherichia coli) and fungi(Candida albicans).Importantly,no obvious cytotoxicity is observed for PVA-CeO_(2)even though the amount of embedded CeO_(2)nanosphere reaches as high as 1.5 wt%.This study reveals new avenues for improving the future smart design of CeO_(2)-based nanoifber membrane composite materials for biological antioxidants.
基金supported by the National Natural Science Foundation of China(No.32272399)the Shanghai Natural Science Foundation(No.21ZR1427500).
文摘Listeria monocytogenes(LM)is a dangerous foodborne pathogen for humans.One emerging and validated method of indirectly assessing LM in food is detecting 3-hydroxy-2-butanone(3H2B)gas.In this study,the synthesis of 3-(2-aminoethylamino)propyltrimethoxysilane(AAPTMS)functionalized hierarchical hollow TiO_(2)nanospheres was achieved via precise controlling of solvothermal reaction temperature and post-grafting route.The sensors based on as-prepared materials exhibited excellent sensitivity(480 Hz@50 ppm),low detection limit(100 ppb),and outstanding selectivity.Moreover,the evaluation of LM with high sensitivity and specificity was achieved using the sensors.Such stable three-dimensional spheres,whose distinctive hierarchical and hollow nanostructure simultaneously improved both sensitivity and response/recovery speed dramatically,were spontaneously assembled by nanosheets.Meanwhile,the moderate loadings of AAPTMS significantly improved the selectivity of sensors.Then,the gas-sensing mechanism was explored by utilizing thermodynamic investigation,Gaussian 16 software,and in situ diffuse reflectance infrared transform spectroscopy,illustrating the weak chemisorption between the-NHgroup and 3H2B molecules.These portable sensors are promising for real-time assessment of LM at room temperature,which will make a magnificent contribution to food safety.
基金supported by National Natural Science Foundation of China(No.52174013)the Fundamental Research Funds for the Central Universities(24CX02004A)+2 种基金Natural Science Foundation of Shandong Province(ZR2024ME105)The Open Fund for Sinopec's Key Laboratory of Ultra-Deep Well Drilling Engineering and Technology(36650000-23-ZC0607-0063)the Fund of State Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China).
文摘In this study, hydrothermal carbon nanospheres(HCNs) were prepared by hydrothermal carbonization using glucose as the precursor, and introduced to improve the properties of water-based drilling fluid for the first time. The variation in rheological and filtration characteristics of water-based drilling fluid with varying concentrations of HCNs were compared between the cases before and after thermal aging. The results demonstrated that HCNs had little influence on the rheological properties of bentonite base mud,but could effectively reduce its filtration loss after thermal aging at 220℃ For polymer-based drilling fluid, HCNs also exhibited minor influence on the rheology. The H-B model was the best fitting model for the rheological curves before thermal aging. After hot rolling at 220℃,the viscosity retention rate increased from 29% to 63%-90% with addition of HCNs, and the filtration loss decreased by 78% with 1.0w/v% HCNs. Meanwhile, the polymer-based drilling fluid with 0.5 w/v% HCNs maintained relatively stable rheology and low filtration loss after statically thermal aging at 200℃ for 96 h. For a bentonitefree water-based drilling fluid prepared mainly with modified natural polymers, the viscosity retention increased from 21% to 74% after hot rolling at 150℃ with 0.5 w/v% HCNs, and was further improved when HCNs and potassium formate were used in combination. The mechanism study revealed that,HCNs could trap dissolved oxygen, scavenge the free radicals and cross link with polymers, which prevented thermal oxidative degradation of polymers and improved the thermal stability of water-based drilling fluid. Meanwhile, HCNs could inhibit clay hydration and swelling in synergy with partially hydrolyzed polyacrylamide by physically sealing the micropores, contributing to shale formation stability.Furthermore, HCNs could effectively improve the lubrication and anti-wear performance of drilling fluid.This study indicated that HCNs could act as green, sustainable, and versatile additives in water-based drilling fluid.
基金financially supported by National Natural Science Foundation of China(Nos.22371086,22071074,21772055)the National Key Research and Development Program(No.2021YFA0716702)+3 种基金the 111 Project(No.B17019)the China Postdoctoral Science Foundation(No.2020 M672388)Self-determined research funds of CCNU from the colleges’basic research and operation of MOE,National Natural Science Foundation of China(No.22006055)the State Key Laboratory of Environmental Chemistry and Ecotoxicology,RCEES,CAS(No.KF2017-4)。
文摘Selective separation of amino acids and proteins is crucial in various areas of research,including proteomics,protein structure and function studies,protein purification and drug development,and biosensing and biodetection.A nanocomposite film is formed by combining layer-by-layer self-assembled gold nanospheres(Au NPs)driven by cucurbit[7]uril(CB[7])and polymethyl methacrylate(PMMA)film.Due to the host-vip interactions,the selective transmission of l-tryptophan in the nanocomposite film is confirmed by the current-voltage measurements using a picoammeter.Furthermore,by adjusting the particle size of Au NPs to increase channel size,lysozyme containing multiple tryptophan residues can selectively pass through the nanocomposite film,indicating the high versatility and adaptability of the nanocomposite film.This study will provide a new direction for the selective separation of amino acids and proteins.
基金financially supported by National Natural Science Foundation of China(22278170,52172058)Natural Science Foundation of Anhui Province(2408085QB037)+3 种基金Natural Science Foundation of Anhui Provincial Department of Education(2023AH020042,2024AH051721)financial support from High-Level Talents Introduction and Cultivation Plan of Anhui Province-Young Top Talent,Huainan Innovation and Entrepreneurship Star Team(HNSTD-2024),Huainan Research Center of New Carbon Energy Materials(HNSPT02)New Energy Materials and Technology Research Center of Huainan Normal University.Business Finland,BATCircle2.0 project(Grant No.44612/31/2020)is acknowledged for financial supportU.L.acknowledges Finnish Research Impact Foundation for Tandem Industry Academy Professorship funding in 2023-2025.
文摘Amorphous transition metal compounds(a-TMC)become one of the most promising pre-catalysts toward oxygen evolution reaction(OER)due to their high-entropy nature and flexible self-reconstruction to highly active derivatives.However,the loosen bonds inside the amorphous structure make it an electronic insulator with unstable structure.Here,monodispersed Ni^(2+)-phytate nanospheres implanted by Fe^(3+)ions(NS_(FeNiPA))were firstly prepared and subsequently transferred into homogeneous high-entropy type Fe-Ni-P-O-C amorphous nanospheres(CNS_(FeNiPO)).It is shown that the CNS_(FeNiPO) presents robust structure and remarkable Fe ions migration during potential-driven activation process,which benefits efficient surface reconstruction and spherical morphology preservation.The CNS_(FeNiPO) with low mass loading of 0.1mg/cm^(2)could deliver small overpotential of 270mV at 10mAcm^(−2)and almost 100%retention of the initial current density after 10h test.The improved electrocatalytic activity is attributed to the boosted electron transfer from Ni sites to O-containing intermediates by introduction of Fe and P atoms.Moreover,rechargeable Zn-air battery with CNS_(FeNiPO)+Pt/C could achieve lower charge potential platform and better cycling performance than that with commercial RuO_(2)+Pt/C.This work provides new insights into the design and understanding of high-entropy amorphous pre-catalysts toward OER.
基金supported by the National Natural Science Foundation of China (No.51973205 and No.51773189)the Fundamental Research Funds for the Central Universities (WK3450000005 and WK3450000006)。
文摘The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported multiple transition metal sulfides(NiWCoS/NC)electrocatalysts were prepared by combining the radiation oxidation synthesis and synchronous carbonization-sulfurization.Initially,the precursor material(NiWCoS/OANI,here OANI refers to oligoaniline)containing sulfurand multiple transition metal(Ni,W,and Co)ions loaded on oligoaniline nanospheres was directly one-pot synthesized at room temperature under γ-ray radiation.Subsequently,NiWCoS/NC electrocatalysts were successfully prepared by calcining the NiWCoS/OANI precursor at 800℃.The electrocatalytic performance of NiWCoS/NC for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)was characterized by electrochemical analysis methods including linear sweep voltammetry,cyclic voltammetry,chronoamperometry,and electrochemical impedance spectroscopy.The influence of the relative content of the loaded transition metals on the electrocatalytic performance was also investigated.The results indicate that the novel NiWCoS/NC electrocatalyst can significantly reduce the overpotential and Tafel slope for both HER and OER compared to corresponding electrocatalysts with single metal or metal sulfide component.When NiWCoS/NC with a molar ratio of 3:6:10 for W,Co,and S elements was used as electrode material,the overpotentials for HER in 0.5 mol/L H_(2)SO_(4) and OER in 1 mol/L KOH are only 161 mV and 243 mV at a current density of 10 mA/cm^(2),respectively.The Tafel slopes are 74 mV/dec and 88 mV/dec,respectively.The work provides a new direction and method for the design and green facile preparation of high-efficiency overall water splitting catalysts.
基金financially supported by the National Natural Science Foundation of China(Nos.51962027 and 21968022)the Major Science and Technology Project of Inner Mongolia Autonomous Region(No.2021ZD0016)+5 种基金the National Key R&D Program of China(No.2020YFC1909105)the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT24002)the Central Guidance Fund for Local Scientific and Technological Development(No.2024ZY0012)the Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00570)the Special Funding of China Postdoctoral Science Foundation(No.2023T160268)the China Postdoctoral Science Foundation(No.2023M741362)
文摘The two-dimensional(2D)layered material molybdenum disulfide(MoS_(2))exhibits a special Mo-S-Mo sandwich structure with a rather large spacing,making it a promising candidate as an anode material for sodium storage applications.Unfortunately,the practical applications are limited by their intrinsically low electrical conductivity,significant volume alteration and severe particle agglomeration.In this study,we designed a new two-step solvothermal strategy to synthesize ultrathin nanosheetassembled MoS_(2)hollow nanospheres strongly located onlignite-based carbon(MoS_(2)/C)without any template.The ultrathin nanosheets assembled into hollow structures mitigated the volume changes of MoS_(2)during the(dis)-charge cycles,facilitated Na+diffusion,and reduced the migration energy barrier within MoS_(2).Lignite-based C enhances the electrical conductivity of MoS_(2),prevents its aggregation,and alleviates mechanical stress during repeated(dis)charging.The resultant hollow spherical MoS_(2)/C composite exhibits outstanding cyclability and rate performance when used as an anode in sodium-ion batteries,as it delivers a high specific capacity of 515.8 mAh g^(-1)after 1000 cycles at 1.0 A g^(-1),with a 94.34%capacity retention rate.Even at a high current density of 20 Ag^(-1),a capacity of 431 mAh g^(-1)can still be obtained after 2000cycles.In particular,the initial Coulombic efficiency of the MoS_(2)anode is markedly enhanced by the incorporation of lignite-based C.
基金supported by National Natural Science Foundation of China(No.22376053)supported by the Natural Science Foundation of Henan Province,China(No.242300421034)Henan Key Scientific Research Programs to Universities and Colleges(No.22ZX003)。
文摘The coating material is considered as the key of solid-phase microextraction(SPME)due to the fact that which has much effect on the selectivity and sensitivity of the analytical method.Herein,the porous hollow carbon nanospheres(PHCNs)were synthesized by selectively removing the interior part of solid inhomogeneous nanospheres with acetone.Using PHCNs as new coating material,a SPME fiber was prepared.To the best of our knowledge,PHCNs was utilized as a SPME fiber coating for the first time.The fiber coating material PHCNs demonstrated excellent thermal stability(>800℃)and long usage lifespan(≥60 times).A headspace SPME(HS-SPME)was established to non-contact extract and enrich polycyclic aromatic hydrocarbons(PAHs)prior to gas chromatography-flame ionization detector(GC-FID)analysis.The HS-SPME not only can eliminate non-volatile interferences from matrix,but also be able to protect fiber coating and prolong lifespan of fiber prober.The linearity in the linear range of 0.01-30 ng/m L and limits of detection from 0.003 ng/mL to 0.006 ng/mL were obtained by HS-SPME-GC-FID with PHCNs as fiber coating.The enrichment factors were calculated as 5420-9211 compared with conventional direct introduce analysis.The spiked recoveries of real samples including campus lake water and lime tree honey were obtained from 80.93%to 118.0%with relative standard deviation no higher than 10.6%.The π-π stacking interaction,CH/π interaction,and unique built-in cavities significantly enhance the extraction performance of PHCNs coating fiber to PAHs.This work demonstrated that the PHCNs as fiber coating materials present good application prospects for the extraction and enrichment of trace PAHs from complex matrixes.
文摘Activating both metal and lattice oxygen sites for efficient oxygen evolution reactions(OER)is a critical challenge.This study pioneers a novel approach,employing cobalt-nickel glycerate solid spheres(CoNi-G SSs)as self-sacrificial templates to synthesize yolk-shell structured CoNi-G SSs@ZIF-67 nanospheres.The derived NiCo2S4@CoS2/MoS2 double-shelled hollow nanospheres integrate the adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM),enabling synergistic dual catalytic pathways.Nickel modulation facilitates active species reconstruction in NiCo_(2)S_(4),enhancing lattice oxygen activity and optimizing the LOM pathway.Characterization results indicate that anode activation triggered the redox processes of metal and lattice oxygen sites,involving the formation and re-filling of oxygen vacancies.Additionally,the CoS_(2)/MoS_(2) heterostructure enhances the AEM pathway,as supported by density functional theory calculations,which demonstrate optimized adsorption of intermediates for both hydrogen evolution reaction and OER.The assembled anion exchange membrane water splitting device can deliver a catalytic current of 500 mA cm^(-2) at 1.74 V under commercial catalytic operating conditions(1 mol L^(-1) KOH)for 150 h,with negligible degradation.This work provides important insights into the understanding of OER mechanisms and the design of high-performance water-splitting electrocatalysts,while also opening new avenues for developing multifunctional materials with multi-shell structures.
基金supported by the Gansu Province Outstanding PhD Student Fund(No.24JRRA206)the National Natural Sci-ence Foundation of China(No.52162040).
文摘Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrinsic electronic structure with d-orbitals fully filled, thus limiting the activation and reduction of CO_(2). To address this issue and maximize the photoreduction of CO_(2), herein we have designed Au@CZS@MO-400 triple-shelled hollow nanospheres by depositing Cd_(0.7)Zn_(0.3)S (CZS) on the outer surface of the MO-400 (MnO_(2) annealed at 400 ℃) hollow nanospheres and then Au nanoparticles on the CZS surface. It is manifested that the resultant 3%Au@CZS@MO-400 achieves a remarkably boosted photoreduction of CO_(2) with the CO/CH_(4) yield rates as high as 68.25/12.42 µmol g^(-1) h^(-1), increased by 3.7/1.5 times over MO-400 and 12.9/1.5 times over CZS. The combined analyses from X-ray photoelectron spectroscopy and density functional theory calculations confirm the creation of electron-deficient Auδ+ active sites by modulating their electron configuration by CZS, consequently decreasing the CO_(2)-Au antibonding-orbital occupancy to reinforce the adsorption strength of CO_(2) onto the Au active sites and in turn boost the photoreduction of CO_(2). Moreover, it is demonstrated that the Au@CZS@MO-400 hollow nanospheres are quite efficient for supplying the Au cocatalyst with photoelectrons for CO_(2) reduction reactions due to the good energy band matching, unique hollow structure and high electron spin polarization of MO-400. This work provides important guidance for understanding and modifying photocatalysts to maximize their photoreduction of CO_(2).
文摘The distribution of ￣(3)H-mitoxantrone polybutyl cyanoacrylate nanospheres(￣(3)H-DHAQ-PBCA-NS)in the viscera,muscle and tumors of human hepatocellular carcinoma (HCC)model in nude mice was studied with liquid scintillation counting techniique. The results showed that the ￣(3)H-DHAQ-PBCA-NS had remarkable liver targeting effect. The content of ￣(3)H-DHAQ-PBCA-NSin liver and heterotopic liver tumor was found to be 71.31±10. 49% of total amount of drug in animal body. It was also found that the content of ￣(3)H-DHAQ-PBCA-NS in liver was higher than that in liver tissue, and the content of ￣(3)H-DHAQ-PBCA-NS in annpit tumor was higher than that in armpit muscle tissue,but had no significant difference;It provides an ideal preparation for the DHAQ admini-stration.
基金the National Natural Science Foundation of China (Grant No. 21701144)the China Postdoctoral Science Foundation (Grant Nos. 2016M592303 and 2017T100536)
文摘Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)).
文摘Objective:To study the biocompatibility and neovascularization of the PLGA nanospheres wrapped with vascular endothelial growth factor(VEGF).which can improve bladder acellular matrix graft(BAMG) with local continuous release of VEGF.Methods:A total of 18 rabbit model (length of stenosis:3cm) with anterior urethral stricture were used as experimental animals and divided into three groups.Group A as the control group:Simple BAMG scaffold materials for urethral reconstruction.Group B as the blank group:PLGA microspheres modified BAMG for urethral reconstruction.Group C:PLGA conjugated with VEGF and modified BAMG for the urethral reconstruction.All rabbits underwent urethral angiography after 7 days,15 days,1 month and 3 months after the operation,and one rabbit in each group was sacrificed to be prepared for the organization histologic examination,HE staining,masson staining,CD31,34 and a-SAM immunohistochemical detection in the repaired sites.Results:In group A,significant urethral restenosis occurred in two rabbits after 15 days of the operation,HE and masson staining showed a lot of collagen arranged in the repaired sites,and there were a large number of inflammatory cell infiltration,and there were also CD31,34 in the repaired sites.a-SAM microvascular tag count showed a small amount of microvascular;Croup B showed anastomotic restenosis,HE and masoon staining showed inflammatory cell infiltration and collagen deposition;Group C:urethrography showed lumen patency.There were a small amount of inflammatory cell infiltration after 7 and 15 days after the operation,and there were also CD31,34 in the repaired sites.The a-SAM microvascular tag count showed many microvascular.And the difference was significant.Conclusions:Anterior urethral reconstruction with sustained-release of VEGF by PLGA nanospheres modified BAMG stents can reduce postoperative restenosis.It can also reduce collagen deposition and scar formation,promote angiogenesis of the repair tissue;therefore it in valuable in the tissue-engineered urethral reconstruction.
基金Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2019R1A2C2088047 and NRF-2020R1C1C1003375).
文摘In this work,a novel vacuum-assisted strategy is proposed to homogenously form Metal-organic frameworks within hollow mesoporous carbon nanospheres(HMCSs)via a solid-state reaction.The method is applied to synthesize an ultrafine CoSe2 nanocrystal@N-doped carbon matrix confined within HMCSs(denoted as CoSe2@NC/HMCS)for use as advanced anodes in highperformance potassium-ion batteries(KIBs).The approach involves a solvent-free thermal treatment to form a Co-based zeolitic imidazolate framework(ZIF-67)within the HMCS templates under vacuum conditions and the subsequent selenization.Thermal treatment under vacuum facilitates the infiltration of the cobalt precursor and organic linker into the HMCS and simultaneously transforms them into stable ZIF-67 particles without any solvents.During the subsequent selenization process,the“dual confinement system”,composed of both the N-doped carbon matrix derived from the organic linker and the small-sized pores of HMCS,can effectively suppress the overgrowth of CoSe2 nanocrystals.Thus,the resulting uniquely structured composite exhibits a stable cycling performance(442 mAh g^−1 at 0.1 A g^−1 after 120 cycles)and excellent rate capability(263 mAh g^−1 at 2.0 A g^−1)as the anode material for KIBs.
基金financially supported by the National Natural Science Foundation of China(No.51202014)。
文摘Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-Sb-Cu nanoparticles have a specific hollow structure with a uniform particle size of 10-20 nm.As there are not any hard templates in the synthesis system,a galvanic displacement reaction mechanism is proposed to account for the formation of the hollow nanostructures.When the alloy powders are used as anode materials for lithium-ion batteries,they exhibit relatively high electrochemical capacity and good cyclic retention.The good electrochemical performance can be attributed to the inactive Cu species.During electrochemical reactions,the inactive copper phase in the hollow structure serves as a soft and ductile matrix,which alleviates the mechanical stresses caused by the severe volume change during lithium insertion and extraction.With their high reversible capacities,the Sn-Sb-Cu alloys are a promising candidate as the anode material of rechargeable lithium-ion batteries.
基金the National Natural Science Foundation of China(52102372,52162007,52163032)China Postdoctoral Science Foundation(2022M712321)the Jiangsu Province Postdoctoral Research Funding Program(2021K473C).
文摘In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.
