A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-bas...A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor has been achieved by depositing the circular W top electrodes on theα-Fe_(2)O_(3)nanosheet arrays.The as-prepared W/α-Fe_(2)O_(3)/ITO memristor shows a reliable nonvolatile bipolar resistive switching behavior with the high resistance ratio of about 103at the reading voltage of 0.1 V,good resistance retention over 10~3s,ultralow set voltage of-0.6 V and reset voltage of 0.7 V,and good durability.In addition,the tunneling conduction mechanism modified by the oxygen vacancies has been proposed and suggested to be responsible for the nonvolatile resistive switching behavior of the as-prepared W/α-Fe_(2)O_(3)/ITO memristor.This work demonstrates that the as-preparedα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor would be a promising candidate for further ultralow power nonvolatile memory applications.展开更多
Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive st...Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented growth.The obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.展开更多
Carbon materials are considered as prospective anode candidates for potassium ion batteries(PIBs).However,the low-rate capability is hampered by slow K+diffusion kinetics and obstructed electron transport of carbon-ba...Carbon materials are considered as prospective anode candidates for potassium ion batteries(PIBs).However,the low-rate capability is hampered by slow K+diffusion kinetics and obstructed electron transport of carbon-based anodes.In this work,calcium D-gluconate derived mesoporous carbon nanosheets(CGC)were interpenetrated into the architecture of reduced graphene oxides(RGO)to form the composites of two-dimensional(2D)/2D graphene/mesoporous carbon nanosheets(RGO@CGC).CGC as a rigid skeleton can prevent the graphene layers from restacking and maintain the structural stability of the 2D/2D carbon composites of RGO@CGC.The mesopores in CGC can shorten the path of ion diffusion and facilitate the penetration of electrolytes.RGO possesses the high surface-to-volume ratio and superior electron transport capability in the honeycomb-like 2D network consisting of sp^(2)-hybridized carbon atoms.Especially,theπ-πstacking interaction between CGC and RGO enhances stable composite structure formation,expedites interlayer-electron transfer,and establishes three-dimensional(3D)ion transportation pathways.Owing to these unique structure,RGO@CGC exhibits fast and stable potassium storage capability.Furthermore,the effects of binders and electrolytes on the electrochemical performance of RGO@CGC were investigated.Finally,Prussian blue was synthesized as a positive electrode to explore the possibility of RGO@CGC as a full battery application.展开更多
Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limite...Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limited therapeutic window of thrombolytic agents,most patients do not receive the drug at the right time.Moreover,these agents are associated with risks of hemorrhage and reperfusion damage.Herein,Angiopep-2(ANG)-black phosphorus(BP)-resveratrol(RES),a drug-loaded system,was used to deliver drugs across the blood–brain barrier(BBB).ANG-BP-RES has a uniform size,stable structure,good photothermal effect,and strong drug release ability under near-infrared(NIR)irradiation and acidic conditions.Furthermore,ANG-BP-RES can efficiently target the brain and improve BBB permeability,exerting a significant therapeutic effect against ischemic brain injury,especially after NIR irradiation.ANG-BP-RES is also biocompatible and shows minimal toxicity toward cells and tissues.This study offers novel insights into the therapeutic management of ischemic brain injury.展开更多
Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thi...Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.展开更多
Herein,we report the self-sacrificial template strategy to design mesoporous layered CeVWO_(x)/TiO_(2)catalysts for the selective catalytic reduction of NO by NH_(3)(NH_(3)-SCR).As-fabricated CeVWO_(x)/TiO_(2)catalyst...Herein,we report the self-sacrificial template strategy to design mesoporous layered CeVWO_(x)/TiO_(2)catalysts for the selective catalytic reduction of NO by NH_(3)(NH_(3)-SCR).As-fabricated CeVWO_(x)/TiO_(2)catalysts with unique mesoporous and layered structure were successfully prepared through the synthesis of Ce,Ti-MOFs by solvothermal method,the impregnation of vanadium and tungsten in Ce,Ti-MOFs and high temperature calcination process.As NH_(3)-SCR catalysts,well-designed CeVWO_(x)/TiO_(2)catalysts exhibit excellent SCR activity with the NO_(x)conversion of over 90%between 210 and 470℃.Meanwhile,CeVWO_(x)/TiO_(2)shows superior tolerance to water vapor and SO_(2).The features of unique mesoporous layered nanostructure,surface acidity,tunable reducibility,active and the strong interaction of active metal oxide and support in CeVWO_(x)/TiO_(2)nanosheets should contribute to the improved SCR performance.In situ diffuse reflection infrared Fourier transform spectroscopy(DRIFTS)analysis indicates that both Langmuir-Hinshelwood(L-H)and Eley-Rideal(E-R)mechanisms are present on the surface of CeVWO_(x)/TiO_(2)at low temperature.This work offers a facile strategy to design and fabricate efficient 2D deNO_x catalyst.展开更多
Small-sized Cd_(x) Zn_(1-x) S solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution(PHE),but it still suffers from easy agglomeration,severe photo corrosion,and fast pho...Small-sized Cd_(x) Zn_(1-x) S solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution(PHE),but it still suffers from easy agglomeration,severe photo corrosion,and fast photogenerated electron-hole recombination.To tackle these issues,herein,we propose a new strategy to modify Cd_(x) Zn_(1-x) S nanoreactors by the simultaneous utilization of ionic-liquid-assisted morphology engineering and MXene-incorporating method.That is,we designed and synthesized a novel hierarchi-cal Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction composite through the in-situ deposition of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets on unique IL-modified Ti_(3) C_(2) MXenes by a one-pot solvothermal method for efficiently PHE.The unique construction strategy tailors the thickness of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets and prevents them from stacking and agglomeration,and especially,optimizes their charge transfer pathways during the photocatalytic process.Compared with pristine Cd_(0.8) Zn_(0.2) S nanosheets,Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) has abun-dant photogenerated electrons available on the Ti_(3) C_(2) surface for proton reduction reaction,owing to the absence of deep-trapped electrons,suppression of electron-hole recombination in Cd_(0.8) Zn_(0.2) S and high-efficiency charge separation at the Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction interface.Moreover,the hy-drophilicity,electrical conductivity,visible-light absorption capacity,and surficial hydrogen desorption of Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) heterostructure are significantly improved.As a result,the heterostructure exhibits out-standing photocatalytic stability and super high apparent quantum efficiency,being rendered as one of the best noble-metal-free Cd-Zn-S-based photocatalysts.This work illustrates the mechanisms of mor-phology control and heterojunction construction in controlling the catalytic behavior of photocatalysts and highlights the great potential of the IL-assisted route in the synthesis of high-performance MXene-based heterostructures for photocatalytic hydrogen evolution.展开更多
Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the ...Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the smooth surface and chemical inertness of aramid fibers. Herein, AP are modified via the nacre-mimetic structure composed of aramid nanofibers (ANF) and carbonylated basalt nanosheets (CBSNs). This is achieved by impregnating AP into an ANF-CBSNs (A-C) suspension containing a 3D ANF framework as the matrix and 2D CBSNs as fillers. The resultant biomimetic composite papers (AP/A-C composite papers) exhibit a layered “brick-and-mortar” structure, demonstrating superior mechanical and electrical insulating properties. Notably, the tensile strength and breakdown strength of AP/A-C5 composite papers reach 39.69 MPa and 22.04 kV mm^(−1), respectively, representing a 155 % and 85 % increase compared to those of the control AP. These impressive properties are accompanied with excellent volume resistivity, exceptional dielectric properties, impressive folding endurance, outstanding heat insulation, and remarkable flame retardance. The nacre-inspired strategy offers an effective approach for producing highly promising electrical insulating papers for advanced electrical equipment.展开更多
It is a big challenge to tune the structure and composition of carbon-based anode materials to increase the active sites by a green synthesis strategy for potassium ion batteries(PIBs).Herein,the N/F/S co-doped three-...It is a big challenge to tune the structure and composition of carbon-based anode materials to increase the active sites by a green synthesis strategy for potassium ion batteries(PIBs).Herein,the N/F/S co-doped three-dimensional(3D)interconnected carbon nanosheets(NFS-CNSs)were synthesized from coal tar pitch(CTP)through a green and low-temperature treatment process for the first time.The as-obtained NFS-CNS600 features 3D interconnected ultra-thin carbon nanosheets with abundant active sites,tunable N/F/S species,and enlarged carbon interlayer spacing.The density functional theory calculation results demonstrate that NFS-CNSs exhibit the highest electron density and most negative K^(+)adsorption energy(-0.59 eV)compared to single or double-atom doping,thereby enhancing the storage performance of K+.As an anode for PIBs,the NFS-CNS600 exhibits good cycle stability(98.2%capacity retention after 200 cycles at 0.2 A g^(-1)),high capacity(409.1 mAh g^(-1) at 0.05 A g^(-1))and rate performance(179.5 mAh g^(-1) at 5 A g^(-1)).Besides,the NFS-CNS600 anode also displays outstanding sodium storage performance.This work offers a green strategy to synthesize CTP-based anode materials from coal chemical by-products for high-performance PIBs.展开更多
The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous...The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous carbon nanosheets doped with both Fe and Ni(Fe/Ni-N-PCNSs)by an easy and template-free approach that solve this problem.Because of their ultrathin porous 2D structure and uniform distribution of Fe and Ni dopants,they capture polysulfides,speed up the sulfur redox reaction,and improve the material’s lithiophilicity,greatly suppressing the shuttling of polysulfides and dendrite growth on the lithium anode.As a result,it has an exceptional performance as a stable host for elemental sulfur and metallic lithium,producing a record long life of 1000 cycles with a very small capacity decay of 0.00025%per cycle in a Li-S battery and an excellent cycling stability of over 850 h with a small overpotential of>72 mV in a lithium metal battery.This work suggests the use of multifunctional-based 2D porous carbon nanosheets as a stable host for both elemental sulfur and metallic lithium to improve the Li-S battery per-formance.展开更多
The slow kinetics of the cathode CO_(2) reduction reaction and the decomposition reaction of Li2CO3,a widebandwidth insulating product,lead to difficult CO_(2) capture and high charging potential in Li-CO_(2) batterie...The slow kinetics of the cathode CO_(2) reduction reaction and the decomposition reaction of Li2CO3,a widebandwidth insulating product,lead to difficult CO_(2) capture and high charging potential in Li-CO_(2) batteries.To improve the reaction kinetics and decrease the reaction overpotential,we synthesized mesoporous Pt nanosheets with high tensile strain.The presence of many unsaturated coordinated Pt atoms around the pores gives rise to tensile strain in the mesoporous Pt nanosheets.This tensile strain plays a key role in regulating the interactions between the catalytic surface of Pt and the adsorbed intermediates.The two-dimensional structure provides more active sites on the surface for the catalytic reactions.These superiorities enable a low overpotential of 0.36 V at a cutoff capacity of 100μAh·cm^(−2) at a current density of 10μA·cm^(−2) over more than 2000 h.This study opens new possibilities for the rational design of metal-based materials with strain engineering for electrochemical energy storage.展开更多
The hydrazine oxidation reaction(HzOR)has garnered significant attention as a feasible approach to replace sluggish anodic reactions to save energy.Nevertheless,there are still difficulties in developing highly effici...The hydrazine oxidation reaction(HzOR)has garnered significant attention as a feasible approach to replace sluggish anodic reactions to save energy.Nevertheless,there are still difficulties in developing highly efficient catalysts for the HzOR.Herein,we report amorphous ruthenium nanosheets(a-Ru NSs)with a thickness of approximately 9.6 nm.As a superior bifunctional electrocatalyst,a-Ru NSs exhibited enhanced electrocatalytic performance toward both the HzOR and hydrogen evolution reaction(HER),outperforming benchmark Pt/C catalysts,where the a-Ru NSs achieved a work-ing potential of merely-76 mV and a low overpotential of only 17 mV to attain a current density of 10 mA·cm^(-2) for the HzOR and HER,respectively.Furthermore,a-Ru NSs displayed a low cell voltage of 28 mV at 10 mA·cm^(-2) for overall hy-drazine splitting in a two-electrode electrolyzer.In situ Raman spectra revealed that the a-Ru NSs can efficiently promote N‒N bond cleavage,thereby producing more*NH_(2)and accelerating the progress of the reaction.展开更多
Utilizing interfacial interaction between different components of a heterojunction to induce defect formation may be an interesting approach for improving the catalytic performance.Here,introducing 3 nm CdS clusters(S...Utilizing interfacial interaction between different components of a heterojunction to induce defect formation may be an interesting approach for improving the catalytic performance.Here,introducing 3 nm CdS clusters(S)on NH_(2)-MIL-125(Ti)nanosheets(NMT-NS)to construct the heterojunction catalysts(Sx/NMT-NS)can induce the generation of abundant defects and Ti^(3+)sites due to the lattice distortion of NMT-NS and the transfer of interfacial charges.These defects and Ti^(3+)sites can chemisorb benzyl alcohol(BZO)molecules through a C–O…Ti coordination while capture and activate O2molecules from air.Furthermore,Z-scheme heterojunction between Cd S clusters and NMT-NS optimizes the transfer and separation of photogenerated electrons-holes,thus accelerating the production of·O_(2)^(-).Therefore,S1.8/NMT-NS achieves a highly efficient conversion of benzylamine(BZA)(>99%)and BZO to N-benzylidene benzylamine(N-BZA)in air atmosphere under visible light,with a selectivity of 99%.Finally,a photocatalytic mechanism involving the activation of reactants molecule and the transfer of photogenerated carriers is propounded at molecular level.展开更多
Smart actuators and wearable and implantable devices have attracted much attention in healthcare and environmental sensing.Flexible electronic and ionic materials are the two main approaches used to construct these de...Smart actuators and wearable and implantable devices have attracted much attention in healthcare and environmental sensing.Flexible electronic and ionic materials are the two main approaches used to construct these devices.Among them,hydrogel-based ionic materials offer unique advantages,such as biocompatibility and adaptable mechanical properties.However,ionic hydrogels encounter challenges in achieving wirelessly powered and noncontact sensing.To address this,we introduce MXene nanosheets to construct ionotronic hydrogels.Leveraging the rich surface charges and electronic conductivity of MXene nanosheets,ionotronic hydrogels can harvest vibrational and electromagnetic waves as electrical energy and enable noncontact sensing.Under ultrasound,it can continuously generate voltages up to 85 V and light up lightemitting diodes,promising wireless charging of implanted devices.In addition,it achieves an absorption coefficient of 0.2 for 915 MHz electromagnetic waves,enabling noncontact sensing through radio frequency identification.Notably,the physically crosslinked network of the MXenebased hydrogels maintained structural and performance stability under ultrasonic stimulation and exhibited self-healing properties.Even when cut into two halves,the self-healing hydrogel fully regenerates its original performance.This study provides insight into the development of ionotronic hydrogels for wirelessly powered and noncontact sensing in smart actuators and wearable and implantable applications.展开更多
The semi-hydrogenation of alkynes to alkenes is of great significance in the industrial production of pharmaceutical and fine chemicals.Electrochemical semi-hydrogenation(ECSH)has emerged as a promising alternative to...The semi-hydrogenation of alkynes to alkenes is of great significance in the industrial production of pharmaceutical and fine chemicals.Electrochemical semi-hydrogenation(ECSH)has emerged as a promising alternative to conventional thermochemical hydrogenation.However,its practical application is hindered by low reaction rate and competing hydrogen evolution reaction(HER).In this work,the controllable incorporation of sulfur into the lattice of Pd nanostructures is proposed to develop disordered and electron-deficient Pd-based nanosheets on Ni foam and enhance their ECSH performance of alkynes.Mechanistic investigations demonstrate that the electronic and geometric structures of Pd sites are optimized by lattice sulfur,which tunes the competitive adsorption of H*and alkynes,inherently inhibits the H*coupling and weakens alkene adsorption,thereby promotes the semi-hydrogenation of alkynes and prevents the over-hydrogenation of alkenes.The optimized Pd-based nanosheets exhibit efficient electrocatalytic semi-hydrogenation performance in an H-cell,achieving 97%alkene selectivity,94%Faradaic efficiency,and a reaction rate of 303.7μmol mgcatal.^(-1) h^(-1) using 4-methoxyphenylacetylene as the model substrate.Even in a membrane electrode assembly(MEA)configuration,the optimized Pd-based nanosheets achieves a single-cycle alkyne conversion of 96%and an alkene selectivity of 97%,with continuous production of alkene at a rate of 1901.1μmol mgcatal.^(-1) h^(-1).The potential-and time-independent selectivity,good substrate universality with excellent tolerance to active groups(C–Br/Cl/C]O,etc.)further highlight the potential of this strategy for advanced catalysts design and green chemistry.展开更多
Emerging two-dimensional MXenes have been extensively studied in a wide range of fields thanks to their superior electrical and hydrophilic attributes as well as excellent chemical stability and mechanical flexibility...Emerging two-dimensional MXenes have been extensively studied in a wide range of fields thanks to their superior electrical and hydrophilic attributes as well as excellent chemical stability and mechanical flexibility.Among them,the ultrahigh electrical conductivity(σ)and tunable band structures of benchmark Ti_(3)C_(2)T_(x) MXene demonstrate its good potential as thermoelectric(TE)materials.However,both the large variation ofσreported in the literature and the intrinsically low Seebeck coefficient(S)hinder the practical applications.Herein,this study has for the first time systematically investigated the TE properties of neat Ti_(3)C_(2)T_(x) films,which are finely modulated by exploiting different dispersing solvents,controlling nanosheet sizes and constructing composites.First,deionized water is found to be superior for obtaining closely packed MXene sheets relative to other polar solvents.Second,a simultaneous increase in both S andσis realized via elevating centrifugal speed on MXene aqueous suspensions to obtain small-sized nanosheets,thus yielding an ultrahigh power factor up to~156μW m^(-1) K^(-2).Third,S is significantly enhanced yet accompanied by a reduction inσwhen constructing MXene-based nanocomposites,the latter of which is originated from the damage to the intimate stackings of MXene nanosheets.Together,a correlation between the TE properties of neat Ti_(3)C_(2)T_(x) films and the stacking of nanosheets is elucidated,which would stimulate further exploration of MXene TEs.展开更多
Two-dimensional(2D)metal-organic frameworks(MOFs)have emerged as promising photosensitizers in photodynamic therapy in recent years.In comparison to bulk MOFs,constructing 2D MOFs can increase the presence of active s...Two-dimensional(2D)metal-organic frameworks(MOFs)have emerged as promising photosensitizers in photodynamic therapy in recent years.In comparison to bulk MOFs,constructing 2D MOFs can increase the presence of active sites through increasing the surface area ratio.Herein,we report a simple solventmediated synthesis method for preparation of 2D porphyrin-based MOF(In-TCPP)nanosheets without the addition of any surfactants as an efficient photosensitizer for enhancing photodynamic antibacterial therapy.The accurate regulation of the morphology and size of 2D In-TCPP nanosheets can be achieved by varying the ratio of water to N,N-dimethylformamide solvent with the appropriate assistance of pyridine.The optimal synthesized 2D In-TCPP nanosheets exhibit a diameter of 70–120 nm and a thickness of 21.5–27.4 nm.Promisingly,2D In-TCPP nanosheets produce a higher amount of ^(1)O_(2) when exposed to660 nm laser compared to the In-TCPP bulk,indicating that the smaller nanosheets possess more active sites for reactive oxygen species generation and can greatly improve the antibacterial photodynamic therapeutic effect.Both the in vitro and in vivo results prove that the In-TCPP nanosheets can be used as a photosensitizer for efficient photodynamic antibacterial therapy to kill S.aureus and promote wound healing.展开更多
Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,a...Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,and 2 h resulted in the deposition of pure nano-sized copper sheets with a length of approximately 500 nm and a thickness of approximately 30 nm,and the production of sulfur particles with an average size of approximately 10μm.The morphology of the cathodic products was significantly influenced by the electrolysis voltage.When Cu_(2)S was introduced into ChCl-TU,it dissolved[CuCl_(2)]^(-)without disrupting the structure of the choline ion(Ch^(+)).As the electrolysis time increased,the copper deposition changed from wire to sheet growth,with the growth direction from radial to epitaxial along the substrate and back to radial.展开更多
Two-dimensional(2D)materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic features.However,the usually-complicated synthesis proce...Two-dimensional(2D)materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic features.However,the usually-complicated synthesis procedures impede in-depth clarification of their catalytic mechanisms.To this end,herein we developed an efficient one-step dimension-reduction carbonization strategy,with which we successfully architected a highly-efficient catalyst for oxygen reduction reaction(ORR),featured with symbiotic cobalt single atoms and clusters decorated in two-dimensional(2D)ultra-thin(3.5 nm thickness)nitrogen-carbon nanosheets.The synergistic effects of the two components afford excellent oxygen reduction activity in alkaline media(E_(1/2)=0.823 V vs.RHE)and thereof a high power density(146.61 mW cm^(-2))in an assembled Zn-air battery.As revealed by theoretical calculations,the cobalt clusters can regulate electrons surrounding those individual atoms and affect the adsorption of intermediate species.As a consequence,the derived active sites of single cobalt atoms lead to a significant improvement of the ORR performance.Thus,our work may fuel interests to delicate architectu re of single atoms and clusters coexisting 2D support toward optimal electrocatalytic performance.展开更多
Black nanosheets(BNs),as a highly promising fracturing-EOR integrated enhancement material,require further study of their huff-n-puff performance and mechanism.This work characterized nanoscale structure,stability,and...Black nanosheets(BNs),as a highly promising fracturing-EOR integrated enhancement material,require further study of their huff-n-puff performance and mechanism.This work characterized nanoscale structure,stability,and interfacial properties of BNs,then evaluated their huff-and-puff performance through NMR-assisted core flooding experiments.The adaptability of BNs in low-permeability reservoirs with different permeabilities,as well as the effect of huff-n-puff cycles on their oil recovery performance,were analyzed.Results show that anionic modified BNs maintained nanoscale flake structure with enhanced electrostatic repulsion.The BNs with an extremely low concentration of 0.002 wt%exhibited excellent emulsification and stabilization effects on crude oil and wettability alteration of the rock surface.Compared with injection water,BNs had excellent huff-n-puff oil recovery effects,reaching 22.1%original oil in place(OOIP)after the first huff-n-puff cycle.BNs had good adaptability in low-permeability cores(i.e.,0.1×10^(−3) to 10×10^(−3)μm^(2)).Increasing the huff-n-puff cycle significantly improved the oil recovery effect of BNs,and the optimal performance was at 4 cycles.As the huff-n-puff cycle increased from 3 to 4,the ability of BNs to“automatic oil-seeking”in micropores became more prominent.This paper also innovatively combined core nuclear magnetic resonance(NMR)T2 analysis,nuclear magnetic imaging analysis,and longitudinal T2 signal analysis along the core(i.e.,along the core injection length).It can not only more accurately quantify the huff-n-puff recovery effect of low-permeability cores but also quantitatively analyze the penetration depth and microscopic huff-n-puff mechanism of BNs from a microscopic perspective.These findings are helpful for the selection of nanomaterials and mechanism analysis in the design of integrated fracturing-flooding schemes and processes.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62341305 and 22269002)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2024GXNSFFA010007)+2 种基金the Science and Technology Project of Guangxi Zhuang Autonomous Region,China(Grant No.AD19110038)the Key Laboratory of AI and Information Processing,Education Department of Guangxi Zhuang Autonomous Region(Grant No.2024GXZDSY015)the Innovation Project of Guangxi University of Science and Technology Graduate Education(Grant No.GKYC202408)。
文摘A facile one-step hydrothermal method has been reported to synthesize theα-Fe_(2)O_(3)nanosheet arrays with the preferred orientation along the[104]direction on the ITO substrate.Theα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor has been achieved by depositing the circular W top electrodes on theα-Fe_(2)O_(3)nanosheet arrays.The as-prepared W/α-Fe_(2)O_(3)/ITO memristor shows a reliable nonvolatile bipolar resistive switching behavior with the high resistance ratio of about 103at the reading voltage of 0.1 V,good resistance retention over 10~3s,ultralow set voltage of-0.6 V and reset voltage of 0.7 V,and good durability.In addition,the tunneling conduction mechanism modified by the oxygen vacancies has been proposed and suggested to be responsible for the nonvolatile resistive switching behavior of the as-prepared W/α-Fe_(2)O_(3)/ITO memristor.This work demonstrates that the as-preparedα-Fe_(2)O_(3)nanosheet arrays-based W/α-Fe_(2)O_(3)/ITO memristor would be a promising candidate for further ultralow power nonvolatile memory applications.
基金Joint Project of Dalian University of Technology-Dalian Institute of Chemical Physics (HX20230236)。
文摘Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented growth.The obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.
基金the financial support from the National Natural Science Foundation of China(No.92163124)Foundation for the Sichuan University and Zigong City Joint research project(No.2021CDZG-2)+1 种基金Foundation for the Sichuan University and Yibin City Strategic Cooperation Project(No.2020CDYB-32)Guangxi Key Laboratory of Low Carbon Energy Material(No.2020GKLLCEM02)。
文摘Carbon materials are considered as prospective anode candidates for potassium ion batteries(PIBs).However,the low-rate capability is hampered by slow K+diffusion kinetics and obstructed electron transport of carbon-based anodes.In this work,calcium D-gluconate derived mesoporous carbon nanosheets(CGC)were interpenetrated into the architecture of reduced graphene oxides(RGO)to form the composites of two-dimensional(2D)/2D graphene/mesoporous carbon nanosheets(RGO@CGC).CGC as a rigid skeleton can prevent the graphene layers from restacking and maintain the structural stability of the 2D/2D carbon composites of RGO@CGC.The mesopores in CGC can shorten the path of ion diffusion and facilitate the penetration of electrolytes.RGO possesses the high surface-to-volume ratio and superior electron transport capability in the honeycomb-like 2D network consisting of sp^(2)-hybridized carbon atoms.Especially,theπ-πstacking interaction between CGC and RGO enhances stable composite structure formation,expedites interlayer-electron transfer,and establishes three-dimensional(3D)ion transportation pathways.Owing to these unique structure,RGO@CGC exhibits fast and stable potassium storage capability.Furthermore,the effects of binders and electrolytes on the electrochemical performance of RGO@CGC were investigated.Finally,Prussian blue was synthesized as a positive electrode to explore the possibility of RGO@CGC as a full battery application.
基金funded by the National Natural Science Foundation of China (No. 81960334)the Guiding Plan of Xinjiang Production Construction Corps (No. 2022ZD007)+4 种基金the Science and Technology Innovation Leading Talents Program of Guangdong Province (No. 2019TX05C343)the Basic and Applied Basic Research Foundation of Guangdong Province-Regional Joint Fund-Key Projects (No. 2019B1515120043)the Project supported by the State Key Laboratory of Luminescence and Applications (No. SKLA-2020-03)the support from Instrumental Analysis Center of Shenzhen University (Xili Campus)Instrumental Analysis Center of Shihezi University.
文摘Ischemic stroke is the leading cause of death in China,accounting for approximately one-third of all stroke-associated deaths worldwide.Currently,thrombolysis is employed for ischemic strokes.However,due to the limited therapeutic window of thrombolytic agents,most patients do not receive the drug at the right time.Moreover,these agents are associated with risks of hemorrhage and reperfusion damage.Herein,Angiopep-2(ANG)-black phosphorus(BP)-resveratrol(RES),a drug-loaded system,was used to deliver drugs across the blood–brain barrier(BBB).ANG-BP-RES has a uniform size,stable structure,good photothermal effect,and strong drug release ability under near-infrared(NIR)irradiation and acidic conditions.Furthermore,ANG-BP-RES can efficiently target the brain and improve BBB permeability,exerting a significant therapeutic effect against ischemic brain injury,especially after NIR irradiation.ANG-BP-RES is also biocompatible and shows minimal toxicity toward cells and tissues.This study offers novel insights into the therapeutic management of ischemic brain injury.
文摘Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.
基金Project supported by National Key Research and Development Plan of China(2021YFB3802003,2022YFB3504102)the Key Research and Development Plan of Jiangsu Province(Social Development,BE2021713)+1 种基金the Six Talent Peaks Project of Jiangsu Province(JNHB-044)the Natural Science Foundation of Jiangsu Province of China(BK20160982)。
文摘Herein,we report the self-sacrificial template strategy to design mesoporous layered CeVWO_(x)/TiO_(2)catalysts for the selective catalytic reduction of NO by NH_(3)(NH_(3)-SCR).As-fabricated CeVWO_(x)/TiO_(2)catalysts with unique mesoporous and layered structure were successfully prepared through the synthesis of Ce,Ti-MOFs by solvothermal method,the impregnation of vanadium and tungsten in Ce,Ti-MOFs and high temperature calcination process.As NH_(3)-SCR catalysts,well-designed CeVWO_(x)/TiO_(2)catalysts exhibit excellent SCR activity with the NO_(x)conversion of over 90%between 210 and 470℃.Meanwhile,CeVWO_(x)/TiO_(2)shows superior tolerance to water vapor and SO_(2).The features of unique mesoporous layered nanostructure,surface acidity,tunable reducibility,active and the strong interaction of active metal oxide and support in CeVWO_(x)/TiO_(2)nanosheets should contribute to the improved SCR performance.In situ diffuse reflection infrared Fourier transform spectroscopy(DRIFTS)analysis indicates that both Langmuir-Hinshelwood(L-H)and Eley-Rideal(E-R)mechanisms are present on the surface of CeVWO_(x)/TiO_(2)at low temperature.This work offers a facile strategy to design and fabricate efficient 2D deNO_x catalyst.
基金financial supports pro-vided by the National Natural Science Foundation of China(No.21905279)the Natural Science Foundation of Fujian Province(No.2020J05086).
文摘Small-sized Cd_(x) Zn_(1-x) S solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution(PHE),but it still suffers from easy agglomeration,severe photo corrosion,and fast photogenerated electron-hole recombination.To tackle these issues,herein,we propose a new strategy to modify Cd_(x) Zn_(1-x) S nanoreactors by the simultaneous utilization of ionic-liquid-assisted morphology engineering and MXene-incorporating method.That is,we designed and synthesized a novel hierarchi-cal Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction composite through the in-situ deposition of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets on unique IL-modified Ti_(3) C_(2) MXenes by a one-pot solvothermal method for efficiently PHE.The unique construction strategy tailors the thickness of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets and prevents them from stacking and agglomeration,and especially,optimizes their charge transfer pathways during the photocatalytic process.Compared with pristine Cd_(0.8) Zn_(0.2) S nanosheets,Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) has abun-dant photogenerated electrons available on the Ti_(3) C_(2) surface for proton reduction reaction,owing to the absence of deep-trapped electrons,suppression of electron-hole recombination in Cd_(0.8) Zn_(0.2) S and high-efficiency charge separation at the Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction interface.Moreover,the hy-drophilicity,electrical conductivity,visible-light absorption capacity,and surficial hydrogen desorption of Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) heterostructure are significantly improved.As a result,the heterostructure exhibits out-standing photocatalytic stability and super high apparent quantum efficiency,being rendered as one of the best noble-metal-free Cd-Zn-S-based photocatalysts.This work illustrates the mechanisms of mor-phology control and heterojunction construction in controlling the catalytic behavior of photocatalysts and highlights the great potential of the IL-assisted route in the synthesis of high-performance MXene-based heterostructures for photocatalytic hydrogen evolution.
基金supported by the National Natural Science Foundation of China(No.22278260)the Open Foundation of Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry(No.KFKT2021-14)Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology(No.KFKT2021-14).
文摘Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the smooth surface and chemical inertness of aramid fibers. Herein, AP are modified via the nacre-mimetic structure composed of aramid nanofibers (ANF) and carbonylated basalt nanosheets (CBSNs). This is achieved by impregnating AP into an ANF-CBSNs (A-C) suspension containing a 3D ANF framework as the matrix and 2D CBSNs as fillers. The resultant biomimetic composite papers (AP/A-C composite papers) exhibit a layered “brick-and-mortar” structure, demonstrating superior mechanical and electrical insulating properties. Notably, the tensile strength and breakdown strength of AP/A-C5 composite papers reach 39.69 MPa and 22.04 kV mm^(−1), respectively, representing a 155 % and 85 % increase compared to those of the control AP. These impressive properties are accompanied with excellent volume resistivity, exceptional dielectric properties, impressive folding endurance, outstanding heat insulation, and remarkable flame retardance. The nacre-inspired strategy offers an effective approach for producing highly promising electrical insulating papers for advanced electrical equipment.
基金the financial supports from the National Natural Science Foundation of China(Nos.52372037 and52072002)the Outstanding Scientific Research and Innovation Team Program of Higher Education Institutions of Anhui Province(No.2023AH010015)+1 种基金the Excellent Young Talents Fund Program of Higher Education Institutions of Anhui Province(No.2023AH030026)the financial support from the Anhui International Research Center of Energy Materials Green Manufacturing and Biotechnology.
文摘It is a big challenge to tune the structure and composition of carbon-based anode materials to increase the active sites by a green synthesis strategy for potassium ion batteries(PIBs).Herein,the N/F/S co-doped three-dimensional(3D)interconnected carbon nanosheets(NFS-CNSs)were synthesized from coal tar pitch(CTP)through a green and low-temperature treatment process for the first time.The as-obtained NFS-CNS600 features 3D interconnected ultra-thin carbon nanosheets with abundant active sites,tunable N/F/S species,and enlarged carbon interlayer spacing.The density functional theory calculation results demonstrate that NFS-CNSs exhibit the highest electron density and most negative K^(+)adsorption energy(-0.59 eV)compared to single or double-atom doping,thereby enhancing the storage performance of K+.As an anode for PIBs,the NFS-CNS600 exhibits good cycle stability(98.2%capacity retention after 200 cycles at 0.2 A g^(-1)),high capacity(409.1 mAh g^(-1) at 0.05 A g^(-1))and rate performance(179.5 mAh g^(-1) at 5 A g^(-1)).Besides,the NFS-CNS600 anode also displays outstanding sodium storage performance.This work offers a green strategy to synthesize CTP-based anode materials from coal chemical by-products for high-performance PIBs.
基金supported by Basic and Applied Basic Research Fund Project of Guangdong(2022A1515011817,2023A1515030160)Research and Innovation Group of Guangdong University of Education(2024KYCXTD014)。
文摘The major problem with lithium-sulfur(Li-S)batteries is their poor cycling stability because of slow redox kinetics in the cathode and the growth of lithium dendrites on the anode.We report the production of 2D porous carbon nanosheets doped with both Fe and Ni(Fe/Ni-N-PCNSs)by an easy and template-free approach that solve this problem.Because of their ultrathin porous 2D structure and uniform distribution of Fe and Ni dopants,they capture polysulfides,speed up the sulfur redox reaction,and improve the material’s lithiophilicity,greatly suppressing the shuttling of polysulfides and dendrite growth on the lithium anode.As a result,it has an exceptional performance as a stable host for elemental sulfur and metallic lithium,producing a record long life of 1000 cycles with a very small capacity decay of 0.00025%per cycle in a Li-S battery and an excellent cycling stability of over 850 h with a small overpotential of>72 mV in a lithium metal battery.This work suggests the use of multifunctional-based 2D porous carbon nanosheets as a stable host for both elemental sulfur and metallic lithium to improve the Li-S battery per-formance.
基金supported by the National Natural Science Foundation of China(52002366,22075263,22571288)the Fundamental Research Funds for the Central Universities(WK2060000091,WK2060250115,WK2060000039)the Students’Innovation and Entrepreneurship Foundation of USTC(CY2023C021).
文摘The slow kinetics of the cathode CO_(2) reduction reaction and the decomposition reaction of Li2CO3,a widebandwidth insulating product,lead to difficult CO_(2) capture and high charging potential in Li-CO_(2) batteries.To improve the reaction kinetics and decrease the reaction overpotential,we synthesized mesoporous Pt nanosheets with high tensile strain.The presence of many unsaturated coordinated Pt atoms around the pores gives rise to tensile strain in the mesoporous Pt nanosheets.This tensile strain plays a key role in regulating the interactions between the catalytic surface of Pt and the adsorbed intermediates.The two-dimensional structure provides more active sites on the surface for the catalytic reactions.These superiorities enable a low overpotential of 0.36 V at a cutoff capacity of 100μAh·cm^(−2) at a current density of 10μA·cm^(−2) over more than 2000 h.This study opens new possibilities for the rational design of metal-based materials with strain engineering for electrochemical energy storage.
基金supported by the National Key R&D Program of China(2018YFA0702001)National Natural Science Foundation of China(22371268,22301287)+3 种基金Fundamental Research Funds for the Central Universities(WK2060000016)Anhui Provincial Natural Science Foundation(2208085J09,2208085QB33)Collaborative Innovation Program of Hefei Science Center,CAS(2022HSC-CIP020)Youth Innovation Promotion Association of the Chinese Academy of Science(2018494)and USTC Tang Scholar.
文摘The hydrazine oxidation reaction(HzOR)has garnered significant attention as a feasible approach to replace sluggish anodic reactions to save energy.Nevertheless,there are still difficulties in developing highly efficient catalysts for the HzOR.Herein,we report amorphous ruthenium nanosheets(a-Ru NSs)with a thickness of approximately 9.6 nm.As a superior bifunctional electrocatalyst,a-Ru NSs exhibited enhanced electrocatalytic performance toward both the HzOR and hydrogen evolution reaction(HER),outperforming benchmark Pt/C catalysts,where the a-Ru NSs achieved a work-ing potential of merely-76 mV and a low overpotential of only 17 mV to attain a current density of 10 mA·cm^(-2) for the HzOR and HER,respectively.Furthermore,a-Ru NSs displayed a low cell voltage of 28 mV at 10 mA·cm^(-2) for overall hy-drazine splitting in a two-electrode electrolyzer.In situ Raman spectra revealed that the a-Ru NSs can efficiently promote N‒N bond cleavage,thereby producing more*NH_(2)and accelerating the progress of the reaction.
基金supported by the National Natural Science Foundation of China(No.22002030)Innovational Found for Scientific and Technological Personnel of Hainan Province(No.NHXXRCXM202301)+1 种基金Collaborative Innovation Center of Ecological Civilization,Hainan University(No.XTCX2022STC11)the Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai(No.AMGM2024F23)。
文摘Utilizing interfacial interaction between different components of a heterojunction to induce defect formation may be an interesting approach for improving the catalytic performance.Here,introducing 3 nm CdS clusters(S)on NH_(2)-MIL-125(Ti)nanosheets(NMT-NS)to construct the heterojunction catalysts(Sx/NMT-NS)can induce the generation of abundant defects and Ti^(3+)sites due to the lattice distortion of NMT-NS and the transfer of interfacial charges.These defects and Ti^(3+)sites can chemisorb benzyl alcohol(BZO)molecules through a C–O…Ti coordination while capture and activate O2molecules from air.Furthermore,Z-scheme heterojunction between Cd S clusters and NMT-NS optimizes the transfer and separation of photogenerated electrons-holes,thus accelerating the production of·O_(2)^(-).Therefore,S1.8/NMT-NS achieves a highly efficient conversion of benzylamine(BZA)(>99%)and BZO to N-benzylidene benzylamine(N-BZA)in air atmosphere under visible light,with a selectivity of 99%.Finally,a photocatalytic mechanism involving the activation of reactants molecule and the transfer of photogenerated carriers is propounded at molecular level.
基金financially supported by the National Natural Science Foundation of China(No.22305033 received by Z.Y.L.,No.52161135102 received by P.Y.W.)the Fundamental Research Funds for the Central Universities(No.2232024A-05 received by Z.Y.L.)。
文摘Smart actuators and wearable and implantable devices have attracted much attention in healthcare and environmental sensing.Flexible electronic and ionic materials are the two main approaches used to construct these devices.Among them,hydrogel-based ionic materials offer unique advantages,such as biocompatibility and adaptable mechanical properties.However,ionic hydrogels encounter challenges in achieving wirelessly powered and noncontact sensing.To address this,we introduce MXene nanosheets to construct ionotronic hydrogels.Leveraging the rich surface charges and electronic conductivity of MXene nanosheets,ionotronic hydrogels can harvest vibrational and electromagnetic waves as electrical energy and enable noncontact sensing.Under ultrasound,it can continuously generate voltages up to 85 V and light up lightemitting diodes,promising wireless charging of implanted devices.In addition,it achieves an absorption coefficient of 0.2 for 915 MHz electromagnetic waves,enabling noncontact sensing through radio frequency identification.Notably,the physically crosslinked network of the MXenebased hydrogels maintained structural and performance stability under ultrasonic stimulation and exhibited self-healing properties.Even when cut into two halves,the self-healing hydrogel fully regenerates its original performance.This study provides insight into the development of ionotronic hydrogels for wirelessly powered and noncontact sensing in smart actuators and wearable and implantable applications.
基金financially supported by the National Natural Science Foundation of China(51701127,92163209,12264053)Shenzhen Fundamental Research Program(JCYJ20220811170904003,JCYJ20210324094000001)+6 种基金Shenzhen Peacock Plan(20180703896C)Shenzhen Key Laboratory of 2D Metamaterials for Information Technology(ZDSYS201707271014468)the research projects of Guangdong Provincial Education Office(2024KCXTD064)ZJUHIC start-up fund(02090200-K02013002)Beijing Natural Science Foundation(JQ22004)the Natural Science Foundation of Hangzhou(2024SZRYBB020001)the Scientific Research and Innovation Project of Postgraduate Students in the Academic Degree of Yunnan University(KC-23234366).
文摘The semi-hydrogenation of alkynes to alkenes is of great significance in the industrial production of pharmaceutical and fine chemicals.Electrochemical semi-hydrogenation(ECSH)has emerged as a promising alternative to conventional thermochemical hydrogenation.However,its practical application is hindered by low reaction rate and competing hydrogen evolution reaction(HER).In this work,the controllable incorporation of sulfur into the lattice of Pd nanostructures is proposed to develop disordered and electron-deficient Pd-based nanosheets on Ni foam and enhance their ECSH performance of alkynes.Mechanistic investigations demonstrate that the electronic and geometric structures of Pd sites are optimized by lattice sulfur,which tunes the competitive adsorption of H*and alkynes,inherently inhibits the H*coupling and weakens alkene adsorption,thereby promotes the semi-hydrogenation of alkynes and prevents the over-hydrogenation of alkenes.The optimized Pd-based nanosheets exhibit efficient electrocatalytic semi-hydrogenation performance in an H-cell,achieving 97%alkene selectivity,94%Faradaic efficiency,and a reaction rate of 303.7μmol mgcatal.^(-1) h^(-1) using 4-methoxyphenylacetylene as the model substrate.Even in a membrane electrode assembly(MEA)configuration,the optimized Pd-based nanosheets achieves a single-cycle alkyne conversion of 96%and an alkene selectivity of 97%,with continuous production of alkene at a rate of 1901.1μmol mgcatal.^(-1) h^(-1).The potential-and time-independent selectivity,good substrate universality with excellent tolerance to active groups(C–Br/Cl/C]O,etc.)further highlight the potential of this strategy for advanced catalysts design and green chemistry.
基金supported by the China Postdoctoral Science Foundation(grant No.2024M750511,J.T.)National Key R&D Program of China(grant No.2022YFB3603804,Y.Z.)National Natural Science Foundation of China(NSFC)under grant Nos.82172470(C.X.)and 22375050(Z.L.).
文摘Emerging two-dimensional MXenes have been extensively studied in a wide range of fields thanks to their superior electrical and hydrophilic attributes as well as excellent chemical stability and mechanical flexibility.Among them,the ultrahigh electrical conductivity(σ)and tunable band structures of benchmark Ti_(3)C_(2)T_(x) MXene demonstrate its good potential as thermoelectric(TE)materials.However,both the large variation ofσreported in the literature and the intrinsically low Seebeck coefficient(S)hinder the practical applications.Herein,this study has for the first time systematically investigated the TE properties of neat Ti_(3)C_(2)T_(x) films,which are finely modulated by exploiting different dispersing solvents,controlling nanosheet sizes and constructing composites.First,deionized water is found to be superior for obtaining closely packed MXene sheets relative to other polar solvents.Second,a simultaneous increase in both S andσis realized via elevating centrifugal speed on MXene aqueous suspensions to obtain small-sized nanosheets,thus yielding an ultrahigh power factor up to~156μW m^(-1) K^(-2).Third,S is significantly enhanced yet accompanied by a reduction inσwhen constructing MXene-based nanocomposites,the latter of which is originated from the damage to the intimate stackings of MXene nanosheets.Together,a correlation between the TE properties of neat Ti_(3)C_(2)T_(x) films and the stacking of nanosheets is elucidated,which would stimulate further exploration of MXene TEs.
基金supported by the National Natural Science Foundation of China(Nos.52102348,22171123,and 22271130)the Science and Technology Innovation Talent Program of University in Henan Province(No.23HASTIT016)+3 种基金the Natural Science Foundation of Henan Province(No.242300420199)International Science and Technology Cooperation Project of Henan Province of China(No.242102520016)the Key Scientific Research Projects of Universities in Henan Province(No.24A350006)the funding support from the National Natural Science Foundation of China-Excellent Young Scientists Fund(Hong Kong and Macao)(No.52122002)。
文摘Two-dimensional(2D)metal-organic frameworks(MOFs)have emerged as promising photosensitizers in photodynamic therapy in recent years.In comparison to bulk MOFs,constructing 2D MOFs can increase the presence of active sites through increasing the surface area ratio.Herein,we report a simple solventmediated synthesis method for preparation of 2D porphyrin-based MOF(In-TCPP)nanosheets without the addition of any surfactants as an efficient photosensitizer for enhancing photodynamic antibacterial therapy.The accurate regulation of the morphology and size of 2D In-TCPP nanosheets can be achieved by varying the ratio of water to N,N-dimethylformamide solvent with the appropriate assistance of pyridine.The optimal synthesized 2D In-TCPP nanosheets exhibit a diameter of 70–120 nm and a thickness of 21.5–27.4 nm.Promisingly,2D In-TCPP nanosheets produce a higher amount of ^(1)O_(2) when exposed to660 nm laser compared to the In-TCPP bulk,indicating that the smaller nanosheets possess more active sites for reactive oxygen species generation and can greatly improve the antibacterial photodynamic therapeutic effect.Both the in vitro and in vivo results prove that the In-TCPP nanosheets can be used as a photosensitizer for efficient photodynamic antibacterial therapy to kill S.aureus and promote wound healing.
基金the financial support from the National Natural Science Foundation of China(Nos.51904005,52304362)the Key Research Foundation of University in Anhui Province,China(No.2023AH051113)+1 种基金the Key Laboratory of Ionic Rare Earth Resources and Environment,Ministry of Natural Resources,China(No.2022IRERE203)the Distinguished Young Research Project of Anhui Higher Education Institution,China(No.2023AH020017)。
文摘Copper nanosheets and sulfur particles were synthesized synchronously by electrolysis,after dissolving Cu_(2)S in ChCl-thiourea(TU)deep eutectic solvent(DES)system.The optimized electrolysis conditions of 0.9 V,80℃,and 2 h resulted in the deposition of pure nano-sized copper sheets with a length of approximately 500 nm and a thickness of approximately 30 nm,and the production of sulfur particles with an average size of approximately 10μm.The morphology of the cathodic products was significantly influenced by the electrolysis voltage.When Cu_(2)S was introduced into ChCl-TU,it dissolved[CuCl_(2)]^(-)without disrupting the structure of the choline ion(Ch^(+)).As the electrolysis time increased,the copper deposition changed from wire to sheet growth,with the growth direction from radial to epitaxial along the substrate and back to radial.
基金supported by the National Natural Science Foundation of China(51872115 and 12234018)Beijing Synchrotron Radiation Facility(BSRF)4B9A.
文摘Two-dimensional(2D)materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic features.However,the usually-complicated synthesis procedures impede in-depth clarification of their catalytic mechanisms.To this end,herein we developed an efficient one-step dimension-reduction carbonization strategy,with which we successfully architected a highly-efficient catalyst for oxygen reduction reaction(ORR),featured with symbiotic cobalt single atoms and clusters decorated in two-dimensional(2D)ultra-thin(3.5 nm thickness)nitrogen-carbon nanosheets.The synergistic effects of the two components afford excellent oxygen reduction activity in alkaline media(E_(1/2)=0.823 V vs.RHE)and thereof a high power density(146.61 mW cm^(-2))in an assembled Zn-air battery.As revealed by theoretical calculations,the cobalt clusters can regulate electrons surrounding those individual atoms and affect the adsorption of intermediate species.As a consequence,the derived active sites of single cobalt atoms lead to a significant improvement of the ORR performance.Thus,our work may fuel interests to delicate architectu re of single atoms and clusters coexisting 2D support toward optimal electrocatalytic performance.
文摘Black nanosheets(BNs),as a highly promising fracturing-EOR integrated enhancement material,require further study of their huff-n-puff performance and mechanism.This work characterized nanoscale structure,stability,and interfacial properties of BNs,then evaluated their huff-and-puff performance through NMR-assisted core flooding experiments.The adaptability of BNs in low-permeability reservoirs with different permeabilities,as well as the effect of huff-n-puff cycles on their oil recovery performance,were analyzed.Results show that anionic modified BNs maintained nanoscale flake structure with enhanced electrostatic repulsion.The BNs with an extremely low concentration of 0.002 wt%exhibited excellent emulsification and stabilization effects on crude oil and wettability alteration of the rock surface.Compared with injection water,BNs had excellent huff-n-puff oil recovery effects,reaching 22.1%original oil in place(OOIP)after the first huff-n-puff cycle.BNs had good adaptability in low-permeability cores(i.e.,0.1×10^(−3) to 10×10^(−3)μm^(2)).Increasing the huff-n-puff cycle significantly improved the oil recovery effect of BNs,and the optimal performance was at 4 cycles.As the huff-n-puff cycle increased from 3 to 4,the ability of BNs to“automatic oil-seeking”in micropores became more prominent.This paper also innovatively combined core nuclear magnetic resonance(NMR)T2 analysis,nuclear magnetic imaging analysis,and longitudinal T2 signal analysis along the core(i.e.,along the core injection length).It can not only more accurately quantify the huff-n-puff recovery effect of low-permeability cores but also quantitatively analyze the penetration depth and microscopic huff-n-puff mechanism of BNs from a microscopic perspective.These findings are helpful for the selection of nanomaterials and mechanism analysis in the design of integrated fracturing-flooding schemes and processes.
