Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The a...Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.展开更多
An in-built N^(+)pocket electrically doped tunnel field-effect transistor(ED-TFET)-based biosensor has been reported for the first time.The proposed device begins with a PN junction structure with a control gate(CG)an...An in-built N^(+)pocket electrically doped tunnel field-effect transistor(ED-TFET)-based biosensor has been reported for the first time.The proposed device begins with a PN junction structure with a control gate(CG)and two polarity gates(PG1 and PG2).Utilizing the polarity bias concept,a narrow N^(+)pocket is formed between the source and channel without the need for additional doping steps,achieved through biasing PG1 and PG2 at-1.2 V and 1.2 V,respectively.This method not only addresses issues related to doping control but also eliminates constraints associated with thermal budgets and simplifies the fabrication process compared to traditional TFETs.To facilitate biomolecule sensing within the device,a nanogap cavity is formed in the gate dielectric by selectively etching a section of the polarity gate dielectric layer toward the source side.The investigation into the presence of neutral and charged molecules within the cavities has been conducted by examining variations in the electrical properties of the proposed biosensor.Key characteristics assessed include drain current,energy band,and electric field distribution.The performance of the biosensor is measured using various metrics such as drain current(I_(DS)),subthreshold swing(SS),threshold voltage(V_(TH)),drain current ratio(I_(ON)/I_(OFF)).The proposed in-built N^(+)pocket ED-TFET-based biosensor reaches a peak sensitivity of 1.08×10~(13)for a neutral biomolecule in a completely filled nanogap with a dielectric constant of 12.Additionally,the effects of cavity geometry and different fill factors(FFs)on sensitivity are studied.展开更多
Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates sign...Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel.展开更多
Hard carbon(HC)in sodium-ion batteries is searched by numerous investigations,which can offer the excellent performance of reversible Na^(+)insertion and extraction.The covalent heteroatom doping in HC is recently wor...Hard carbon(HC)in sodium-ion batteries is searched by numerous investigations,which can offer the excellent performance of reversible Na^(+)insertion and extraction.The covalent heteroatom doping in HC is recently worth concentrating,which can dilate the interlayer spacing of graphite to adjust the electrochemical storage performance in carbon anodes.However,the reported doping strategies of the modified HC have only resulted in limited improvement,especially unobvious effects on tuning porous structure.In this study,tannin extract and K_(2)SO_(4) are respectively utilized as carbon source and sulfur source for the fabrication of HC,in which K_(2)SO_(4) can contribute to the heteroatom doping,and the pore forming as well.The tannin-derived sulfur-doped carbon anode shows the excellent cycle stability,achieving a high reversible capacity of 520.5 mAh/g at a current density of 100 mA/g.Even after 500 cycles at a current density of 3 A/g,a high specific capacity of 236.7 mAh/g and a capacity retention rate of 92.6%can be reserved.Compared with the initial carbon,the adsorption energy of Na^(+)is multifold times higher,whereas Na^(+)diffusion energy barriers manyfold decrease.Moreover,the full battery assembled with Na_(3)V_(2)(PO_(4))_(3)/tannin-based HC demonstrates a stable cycling performance.This work can manifest the potentiality of the tannin-based electrode as anode for a high-performance sodium-ion batteries(SIBs),which could especially offer an explanation of Na^(+)storage and solid-electrolyte interface(SEI)stability to the electrochemical performance.展开更多
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes...Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.展开更多
β-Ga_(2)O_(3)is a promising candidate for solarblind ultraviolet photodetection owing to its suitable bandgap of approximately 4.9 eV,excellent photoresponse characteristics,and high stability.However,the lack of a s...β-Ga_(2)O_(3)is a promising candidate for solarblind ultraviolet photodetection owing to its suitable bandgap of approximately 4.9 eV,excellent photoresponse characteristics,and high stability.However,the lack of a sufficient driving force within the material leads to extensive bulk charge recombination,limiting its photocurrent and thus posing significant challenges in designing high-performance Ga_(2)O_(3)-based photodetection.In this study,we propose a gradient doping strategy to achieve a Sn-doping concentration gradient along theβ-Ga_(2)O_(3)film thickness.By combining sol-gel synthesis with rapid thermal annealing,a spatially graded band structure with a full-space built-in electric field is constructed,which increases the width of band bending over a large region and is crucial for significantly enhancing carrier separation and transport in the bulk.The resulting gradient Sn-dopedβ-Ga_(2)O_(3)enables exceptional photoelectric performance without an external bias under 254 nm irradiation,including a superior responsivity of 66.88 mA W^(-1),a high detectivity of 8.12×10^(11)Jones,and a fast rise/decay time of 79/65 ms,outstanding most existing similar reported photoelectrochemical(PEC)type optoelectronic devices.Additionally,the device exhibits excellent long-term stability and enables high-resolution underwater ultraviolet imaging.This study demonstrates that the gradient doping strategy provides a feasible approach for enhancing the PEC performance ofβ-Ga_(2)O_(3)photoelectrodes.展开更多
MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper...MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.展开更多
The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batte...The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).展开更多
Electrochemical CO_(2) reduction reaction(CO_(2)RR) into valuable formate provides a strategy for carbon neutrality.Bismuth(Bi) catalysts,attributed to their appropriate energy barrier of OCHO*intermediate,have demons...Electrochemical CO_(2) reduction reaction(CO_(2)RR) into valuable formate provides a strategy for carbon neutrality.Bismuth(Bi) catalysts,attributed to their appropriate energy barrier of OCHO*intermediate,have demonstrated substantial potential for the advancement of electrocatalytic CO_(2) reduction to formate.However,due to the weak bonding of protons(H^(*)) of Bi,the available protonate of CO_(2) on Bi is insufficient,which limits the formation of OCHO^(*).Prediction by theoretical calculation,chlorine doping can effectively promote the dissociation of H_(2)O and thus achieve effective proton supply.We prepare chlorine-doped Bi(Cl-Bi) via an electrochemical conversion strategy for electroreduction of CO_(2) .An obvious improvement of faradaic efficiency(FE) of formate(96.7% at-0.95 V vs.RHE) can be achieved on Cl-Bi,higher than that of Bi(89.4%).Meanwhile,Cl-Bi has the highest formate production rate of 275 μmol h^(-1)cm^(-2)at-0.95 V vs.RHE,which is 1.2 times higher than that of Bi(224 μmol h^(-1)cm^(-2)).In situ characterizations and kinetic analysis reveal that chlorine doping promotes the activation of H_(2)O and supply sufficient protons to promote the protonation of CO_(2) to OCHO^(*),which is consistent with theoretical calculation.The study presents an effective strategy for rational design of highly efficient electrocatalysts to promote green chemical production.展开更多
We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron...We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron hopping parameters,the strong-coupling pseudogap in the two-dimensional Hubbard model can be either enhanced or suppressed in the doped Mott insulator regime.We find that in underdoped cases,the closing of pseudogap leads to a significant enhancement of superconductivity,indicating competition between the two in the underdoped regime.In contrast,at large dopings,suppressing the pseudogap is accompanied by a concurrent decrease in the superconducting transition temperature Tc,which can be attributed to a reduction in antiferromagnetic correlations behind both the pseudogap and superconductivity.We elucidate this evolving relationship between pseudogap and superconductivity across different doping regimes.展开更多
By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering met...By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering method in pure argon and pure oxygen gas,respectively.The crystal structure,morphological characteristics,composition and optical properties of the obtained films were compared by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and ultraviolet(UV)-visible spectrophotometer.The properties of the thin films deposited in different sputtering gases are quite different.For the films deposited in pure argon gas,it is a polycrystalline thin film with(200)preferred orientation,while the film deposited in pure oxygen has no preferred orientation.The grain size,molar ratio of Mg to Ni atoms and optical bandgap are larger for the films deposited in pure argon gas than those deposited in oxygen gas.展开更多
Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high curr...Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.展开更多
In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ...In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.展开更多
We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.C...We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1).展开更多
N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demo...N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.展开更多
The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and exper...The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.展开更多
Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared...Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared(NIR)excitation to produce efficient photon conversion.It has been established that ytterbium(Yb^(3+))may improve the performance of EFMs in both bulk and nanostructured forms by energy transfer channels among rare-earth ions in interstitial clusters.In this work,a comprehensive analysis of the Er^(3+):Yb^(3+):CaF_(2)crystalline structure,photoluminescence,and energy transfer from Yb^(3+)to Er^(3+)is presented for powders prepared by combustion synthesis.The Er^(3+):Yb^(3+):CaF_(2)powders display exceptional photon down-shift and up-conversion when exposed to NIR light(λ=975 nm).The luminescence spectral change of the NIR emission around 1.5μm,which corresponds to the Er^(3+)electronic transition ^(4)I_(13/2)→^(4)I_(15/2),was investigated in a temperature range of 298-423 K for application in temperature sensing of biological systems exploring the third biological window.The luminescence intensity ratio technique was applied to the thermally coupled Stark sublevels of states^(4)I_(13/2)and^(4)I_(15/2)with the highest estimated temperature relative sensitivity being around 0.4%/K at 298 K.展开更多
Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical...Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical conductivity and significant volume changes have limited their electrochemical stability and practical application performance.This work proposes a universal doping strategy for the preparation of tin-phthalic acid complexes(Sn-MOF)doped with metal atoms(Al,Cr,Mn,Fe,Co,Ni,Cu,Zn).Metal atoms are uniformly dispersed within Sn-MOF for enhancing electrical conductivity and accommodating appropriate volume expansion,resulting in improved rate capability and cycling stability.Additionally,compared to a series of doped Sn-MOF,Zn-doped Sn-MOF exhibits the most exceptional electrochemical performance with a high reversible capacity of 1131 mAh·g^(-1)and stable cycling performance at a current density of 0.5 A·g^(-1),delivering a capacity of 1065 mAh·g^(-1)after 500 cycles.Zn-doping catalyzes the lithiation reaction between Sn-MOF and Li^(+),promoting their reaction kinetics during the first cycle.Furthermore,the Zn-doped Sn-MOF is inclined to form a thin and stable solid electrolyte interface film to maintain cyclic stability.展开更多
Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and ...Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and electrolyte materials,thereby impeding commercialization.Anion doping emerges as a promising strategy to enhance the electrochemical efficiency of perovskite-based cathodes and electrolytes.However,integrating this approach within a single-cell structure still requires further research.In this study,F-doped perovskite oxides BaCo_(0.4)Fe_(0.4)Zr_(0.1)Y_(0.1)O_(2.9-δ)F_(0.1)(BCFZYF)and BaZr_(0.1)Ce_(0.7)Y_(0.1)Yb_(0.1)O_(2.9-δ)F_(0.1)(BZCYYbF)were synthesized for use as the cathode and electrolyte,respectively,in proton ceramic fuel cells.Our findings demonstrate that F-doped perovskite oxides exhibit superior electrochemical performance and enhanced structural stability.Furthermore,doping both electrodes and electrolytes with F ions improves their interfacial compatibility.The cell configuration BCFZYF|BZCYYbF|Ni-BZCYYbF achieved a peak power density of 998 mW·cm^(−2)at 650℃using H_(2)as fuel,and it maintained stable operation for over 400 h at 550℃with a current density of 400 mA·cm^(−2).This research underscores an effective strategy for enhancing the performance and durability of proton ceramic fuel cells.展开更多
Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facet...Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.展开更多
文摘Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system.
基金Project supported by the Ministry of Education’s Supply and Demand Matching Employment and Education Project(Grant No.2024110776329)。
文摘An in-built N^(+)pocket electrically doped tunnel field-effect transistor(ED-TFET)-based biosensor has been reported for the first time.The proposed device begins with a PN junction structure with a control gate(CG)and two polarity gates(PG1 and PG2).Utilizing the polarity bias concept,a narrow N^(+)pocket is formed between the source and channel without the need for additional doping steps,achieved through biasing PG1 and PG2 at-1.2 V and 1.2 V,respectively.This method not only addresses issues related to doping control but also eliminates constraints associated with thermal budgets and simplifies the fabrication process compared to traditional TFETs.To facilitate biomolecule sensing within the device,a nanogap cavity is formed in the gate dielectric by selectively etching a section of the polarity gate dielectric layer toward the source side.The investigation into the presence of neutral and charged molecules within the cavities has been conducted by examining variations in the electrical properties of the proposed biosensor.Key characteristics assessed include drain current,energy band,and electric field distribution.The performance of the biosensor is measured using various metrics such as drain current(I_(DS)),subthreshold swing(SS),threshold voltage(V_(TH)),drain current ratio(I_(ON)/I_(OFF)).The proposed in-built N^(+)pocket ED-TFET-based biosensor reaches a peak sensitivity of 1.08×10~(13)for a neutral biomolecule in a completely filled nanogap with a dielectric constant of 12.Additionally,the effects of cavity geometry and different fill factors(FFs)on sensitivity are studied.
文摘Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel.
基金supported by National Natural Science Foundation of China(Nos.32271791,32171709 and 22475053)Hunan Provincial Natural Science Foundation of China(No.2024JJ7643)Natural Science Foundation of Shanghai(No.22ZR1404100).
文摘Hard carbon(HC)in sodium-ion batteries is searched by numerous investigations,which can offer the excellent performance of reversible Na^(+)insertion and extraction.The covalent heteroatom doping in HC is recently worth concentrating,which can dilate the interlayer spacing of graphite to adjust the electrochemical storage performance in carbon anodes.However,the reported doping strategies of the modified HC have only resulted in limited improvement,especially unobvious effects on tuning porous structure.In this study,tannin extract and K_(2)SO_(4) are respectively utilized as carbon source and sulfur source for the fabrication of HC,in which K_(2)SO_(4) can contribute to the heteroatom doping,and the pore forming as well.The tannin-derived sulfur-doped carbon anode shows the excellent cycle stability,achieving a high reversible capacity of 520.5 mAh/g at a current density of 100 mA/g.Even after 500 cycles at a current density of 3 A/g,a high specific capacity of 236.7 mAh/g and a capacity retention rate of 92.6%can be reserved.Compared with the initial carbon,the adsorption energy of Na^(+)is multifold times higher,whereas Na^(+)diffusion energy barriers manyfold decrease.Moreover,the full battery assembled with Na_(3)V_(2)(PO_(4))_(3)/tannin-based HC demonstrates a stable cycling performance.This work can manifest the potentiality of the tannin-based electrode as anode for a high-performance sodium-ion batteries(SIBs),which could especially offer an explanation of Na^(+)storage and solid-electrolyte interface(SEI)stability to the electrochemical performance.
基金supported by the National Natural Science Foundation of China (No.52274304)。
文摘Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer.
基金supported by the National Natural Science Foundation of China(12304102,62574029)Natural Science Foundation of Chongqing(CSTB2023NSCQ-MSX0479)+1 种基金Science and Technology Research Project of Chongqing Education Committee(KJQN202400558)Doctoral Scientific Research Fund of Chongqing Normal University(23XLB029)。
文摘β-Ga_(2)O_(3)is a promising candidate for solarblind ultraviolet photodetection owing to its suitable bandgap of approximately 4.9 eV,excellent photoresponse characteristics,and high stability.However,the lack of a sufficient driving force within the material leads to extensive bulk charge recombination,limiting its photocurrent and thus posing significant challenges in designing high-performance Ga_(2)O_(3)-based photodetection.In this study,we propose a gradient doping strategy to achieve a Sn-doping concentration gradient along theβ-Ga_(2)O_(3)film thickness.By combining sol-gel synthesis with rapid thermal annealing,a spatially graded band structure with a full-space built-in electric field is constructed,which increases the width of band bending over a large region and is crucial for significantly enhancing carrier separation and transport in the bulk.The resulting gradient Sn-dopedβ-Ga_(2)O_(3)enables exceptional photoelectric performance without an external bias under 254 nm irradiation,including a superior responsivity of 66.88 mA W^(-1),a high detectivity of 8.12×10^(11)Jones,and a fast rise/decay time of 79/65 ms,outstanding most existing similar reported photoelectrochemical(PEC)type optoelectronic devices.Additionally,the device exhibits excellent long-term stability and enables high-resolution underwater ultraviolet imaging.This study demonstrates that the gradient doping strategy provides a feasible approach for enhancing the PEC performance ofβ-Ga_(2)O_(3)photoelectrodes.
基金support from the Key projects of scientific research projects of universities in Anhui Province(2024AH050360).
文摘MnO_(2) stands out among cathode materials for aqueous zinc-ion batteries(AZIBs)high capacity and voltage,it has poor stability and slow Zn^(2+) kinetics.Herein,we propose a dual-regulation strategy integrating copper doping and carbon-based confinement.Residual carbon(RC),derived from acid-washed coal gasification fine slag(CGFS),serves as a conductive and porous framework for the directional growth of Cu-doped MnO_(2) nanowires(CMO@RC).The synergistic modulation of Cu-induced electronic structure tuning and carbon confinement induced mechanical/electrical stabilization significantly enhances Zn^(2+) transport and electrochemical performance.CMO@RC achieves a high capacity of 563 mA·h·g^(−1) at 0.1 A·g^(−1) and maintains 106%after 1000 cycles at 1 A·g^(−1).Kinetic analyses confirm the dual-path Zn^(2+) diffusion and accelerated reaction kinetics,while DFT calculations reveal that Cu doping enhances Mn 3d orbital hybridization and electron interaction with carbon,elevating the density of states near the Fermi level and reducing charge transfer barriers.Furthermore,pouch cell testing demonstrates outstanding flexibility and mechanical resilience.This study provides a cost-effective and scalable strategy for high-performance AZIBs,leveraging both experimental and theoretical validations.
基金supported by the Low-Cost Long-Life Batteries program,China(No.WL-24-08-01)the National Natural Science Foundation of China(No.22279007)。
文摘The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).
基金financially supported by the Natural Science Foundation of Shandong Province (No.ZR2022QE076)the National Natural Science Foundation of China (No.52202092)the Science and Technology Support Plan for Youth Innovation of Colleges and Universities of Shandong Province of China (No.2023KJ104)。
文摘Electrochemical CO_(2) reduction reaction(CO_(2)RR) into valuable formate provides a strategy for carbon neutrality.Bismuth(Bi) catalysts,attributed to their appropriate energy barrier of OCHO*intermediate,have demonstrated substantial potential for the advancement of electrocatalytic CO_(2) reduction to formate.However,due to the weak bonding of protons(H^(*)) of Bi,the available protonate of CO_(2) on Bi is insufficient,which limits the formation of OCHO^(*).Prediction by theoretical calculation,chlorine doping can effectively promote the dissociation of H_(2)O and thus achieve effective proton supply.We prepare chlorine-doped Bi(Cl-Bi) via an electrochemical conversion strategy for electroreduction of CO_(2) .An obvious improvement of faradaic efficiency(FE) of formate(96.7% at-0.95 V vs.RHE) can be achieved on Cl-Bi,higher than that of Bi(89.4%).Meanwhile,Cl-Bi has the highest formate production rate of 275 μmol h^(-1)cm^(-2)at-0.95 V vs.RHE,which is 1.2 times higher than that of Bi(224 μmol h^(-1)cm^(-2)).In situ characterizations and kinetic analysis reveal that chlorine doping promotes the activation of H_(2)O and supply sufficient protons to promote the protonation of CO_(2) to OCHO^(*),which is consistent with theoretical calculation.The study presents an effective strategy for rational design of highly efficient electrocatalysts to promote green chemical production.
基金supported by the National Natural Science Foundation of China(Grant Nos.12274472,12494594,12494591,and 92165204)National Key Research and Development Program of China(Grant No.2022YFA1402802)+2 种基金Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices(Grant No.2022B1212010008)Guangdong Fundamental Research Center for Magnetoelectric Physics(Grant No.2024B0303390001)Guangdong Provincial Quantum Science Strategic Initiative(Grant No.GDZX2401010)。
文摘We investigate the interplay between the pseudogap state and d-wave superconductivity in the two-dimensional doped Hubbard model by employing an eight-site cluster dynamical mean-field theory method.By tuning electron hopping parameters,the strong-coupling pseudogap in the two-dimensional Hubbard model can be either enhanced or suppressed in the doped Mott insulator regime.We find that in underdoped cases,the closing of pseudogap leads to a significant enhancement of superconductivity,indicating competition between the two in the underdoped regime.In contrast,at large dopings,suppressing the pseudogap is accompanied by a concurrent decrease in the superconducting transition temperature Tc,which can be attributed to a reduction in antiferromagnetic correlations behind both the pseudogap and superconductivity.We elucidate this evolving relationship between pseudogap and superconductivity across different doping regimes.
基金supported by the Jilin Provincial Scientific and Technological Development Program(No.20220101036JC)。
文摘By doping with Mg atoms,the bandgap of Mg-doped NiO thin films can be adjusted larger.By using NiO and MgO as sputtering targets,Mg-doped NiO thin films were deposited using radio-frequency magnetron co-sputtering method in pure argon and pure oxygen gas,respectively.The crystal structure,morphological characteristics,composition and optical properties of the obtained films were compared by X-ray diffraction(XRD),scanning electron microscope(SEM),energy dispersive spectrometer(EDS)and ultraviolet(UV)-visible spectrophotometer.The properties of the thin films deposited in different sputtering gases are quite different.For the films deposited in pure argon gas,it is a polycrystalline thin film with(200)preferred orientation,while the film deposited in pure oxygen has no preferred orientation.The grain size,molar ratio of Mg to Ni atoms and optical bandgap are larger for the films deposited in pure argon gas than those deposited in oxygen gas.
基金National Natural Science Foundation of China(No.22272149,22062025)Yunnan University’s Research Innovation Fund for Graduate Students(No.KC-23234085)+1 种基金Workstation of Academician Chen Jing of Yunnan Province(No.202105AF150012)Free Exploration Fund for Academician(No.202405AA350001)。
文摘Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.
基金supported by the Guangdong Basic and Applied Basic Research Foundation (No.2023A1515010093)the Shenzhen Fundamental Research Program (Stable Support Plan Program)(Nos.JCYJ20220809170611004, 20231121110828001 and 20231121113641002)the National Taipei University of Technology-Shenzhen University Joint Research Program (No.2024001)。
文摘In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers.
基金supported by the National Natural Science Foundation of China (Grant No.22063010)the Natural Science Foundation of Shaanxi Province (Grant No.2022QFY07-05)Yan'an Science and Technology Plan Project (Grants No.2022SLJBZ-002, 2023-CYL-193)。
文摘We used the natural product chamomile as a carbon source to synthesize praseodymium(Pr) and nitrogen(N) co-doped biomass carbon dots(Pr/N-BCDs) with remarkable luminescence properties by one-step hydrothermal method.Compared with single N-doped BCDs(N-BCDs) and Pr-doped BCDs(Pr-BCDs),Pr/N-BCDs not only showed better fluorescence properties and stability but also achieved a significant increase in quantum yield of 12%.More importantly,under certain conditions,Pr/N-BCDs and 2,4-dinitrophenylhydrazide(2,4-DNPH) had significant fluorescence internal filtration effect(IFE) and dynamic quenching effect,and in the concentration range of0.50-20 μmol·L^(-1),the concentration of 2,4-DNPH had a good linear relationship with the fluorescence quenching signal,and the detection limit was as low as 2.1 nmol·L^(-1).
基金the financial support from Sichuan Science and Technology Program(No.2023NSFSC0847)Scientific Research and Innovation Team Program of Sichuan University of Science and Technology(No.SUSE652A003)+3 种基金Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC03)Talent Introduction Project of Sichuan University of Science and Engineering(No.2021RC05)the Undergraduate Training Program for Innovation and Entrepreneurship(No.CX2024042)The Innovation Fund of Postgraduate,Sichuan University of Science&Engineering(No.Y2024094)。
文摘N-doped graphite carbon sphere coated cobalt nanoparticle catalyst(Co@C-N-900),prepared by solvothermal-calcination method,is applied to activate peroxymonosulfate(PMS)for bisphenol A(BPA)elimination.The outcomes demonstrate that the Co@C-N-900 could effectively activate PMS,thereby causing efficient removal of BPA in water.In addition,the Co@C-N-900/PMS system also has the advantages of low metal leaching,applicability in high salinity environments,good selectivity and stability.Further investigations using electron paramagnetic resonance,chronoamperometry,and quenching experiments demonstrated that the Co@C-N-900/PMS system is a typical non-radical route with singlet oxygen(^(1)O_(2))as the main reactive oxygen species(ROS).Density functional theory calculations(DFT)indicate that N-doping can effectively regulate the charge distribution on the catalyst surface,generating acidic/alkaline sites favorable for PMS adsorption and activation.Furthermore,it also can enhance the interaction and charge transfer capacity between the Co@C-N-900 and PMS.Lastly,LC-QTOF-MS/MS analysis revealed two possible BPA degradation pathways:(1)^(1)O_(2)attacked the isopropyl group in BPA between the two phenyl groups,causingβ-scission to occur.(2)Following the oxidation of the hydroxyl group in the aromatic ring of BPA,^(1)O_(2)could cause furtherβ-scission.The prepared Co@C-N-900 catalyst is a very promising catalyst,which would offer a workable remedy for treating water pollution.
基金supported by the Open Project of Xiangjiang Laboratory (22XJ03026)the National Natural Science Foundation of China (72004060)+3 种基金the Provincial Natural Science Foundation of Hunan Province (2022JJ30015)the Scientific Research Project of Hunan Education Department, China (23A0457)Environmental Protection Scientific Research Project of Hunan Province (HBKT2021021)the “Digital-intelligence+” interdisciplinary research project of Hunan University of Technology and Business (2023SZJ22)
文摘The objective of this study was to identify and synthesize functional groups for the efficient adsorption of volatile organic compounds(VOCs)through a combination of theoretical calculations,molecular design,and experimental validation.The density functional theory(DFT)calculation,focusing on the P-containing functional groups,showed that methanol adsorption was dominated by the electrostatic interaction between the carbon surface and methanol,while toluene was mainly trapped through π-π dispersive interaction between toluene molecule and functional group structure.The experimental results showed the phosphorus-doped carbon materials(PCAC)prepared by directly activating potassium phytate had a phosphorus content of up to 4.5%(atom),mainly in the form of C-O-P(O)(OH)_(2).The material exhibited a high specific area(987.6m^(2)·g^(-1))and a large adsorption capacity for methanol(440.0 mg·g^(-1))and toluene(350.1 mg·g^(-1)).These properties were superior to those of the specific commercial activated carbon(CAC)sample used for comparison in this study.The adsorption efficiencies per unit specific surface area of PCAC were 0.45 mg·g^(-1) m^(-2) for methanol and 0.35 mg·g^(-1)·m^(-2) for toluene.This study provided a novel theoretical and experimental framework for the molecular design of polarized elements to enhance the adsorption of polar gases,offering significant advancements over existing commercial solutions.
基金Project supported in part by the Brazilian Agency Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)。
文摘Luminescent materials for application in temperature sensing have caught a lot of interest in recent years.Particularly erbium(Er^(3+))-doped fluoride-based materials(EFM),which are readily accessible by near-infrared(NIR)excitation to produce efficient photon conversion.It has been established that ytterbium(Yb^(3+))may improve the performance of EFMs in both bulk and nanostructured forms by energy transfer channels among rare-earth ions in interstitial clusters.In this work,a comprehensive analysis of the Er^(3+):Yb^(3+):CaF_(2)crystalline structure,photoluminescence,and energy transfer from Yb^(3+)to Er^(3+)is presented for powders prepared by combustion synthesis.The Er^(3+):Yb^(3+):CaF_(2)powders display exceptional photon down-shift and up-conversion when exposed to NIR light(λ=975 nm).The luminescence spectral change of the NIR emission around 1.5μm,which corresponds to the Er^(3+)electronic transition ^(4)I_(13/2)→^(4)I_(15/2),was investigated in a temperature range of 298-423 K for application in temperature sensing of biological systems exploring the third biological window.The luminescence intensity ratio technique was applied to the thermally coupled Stark sublevels of states^(4)I_(13/2)and^(4)I_(15/2)with the highest estimated temperature relative sensitivity being around 0.4%/K at 298 K.
基金support from Natural Science Foundations of Henan Province(Nos.222300420502 and 232300420093)the Program for Science and Technology Innovation Talents in Universities of Henan Province(No.24HASTIT006)the Key Science and Technology Program of Henan Province(No.222102240044)。
文摘Tin-based metal organic complexes with breakable coordination bonds,multiple active sites,and high theoretical capacity have attracted wide attentiorials for lithium-ion batteries(LIBs).However,the inferior electrical conductivity and significant volume changes have limited their electrochemical stability and practical application performance.This work proposes a universal doping strategy for the preparation of tin-phthalic acid complexes(Sn-MOF)doped with metal atoms(Al,Cr,Mn,Fe,Co,Ni,Cu,Zn).Metal atoms are uniformly dispersed within Sn-MOF for enhancing electrical conductivity and accommodating appropriate volume expansion,resulting in improved rate capability and cycling stability.Additionally,compared to a series of doped Sn-MOF,Zn-doped Sn-MOF exhibits the most exceptional electrochemical performance with a high reversible capacity of 1131 mAh·g^(-1)and stable cycling performance at a current density of 0.5 A·g^(-1),delivering a capacity of 1065 mAh·g^(-1)after 500 cycles.Zn-doping catalyzes the lithiation reaction between Sn-MOF and Li^(+),promoting their reaction kinetics during the first cycle.Furthermore,the Zn-doped Sn-MOF is inclined to form a thin and stable solid electrolyte interface film to maintain cyclic stability.
基金supported by the National Natural Science Foundation of China(No.22278203)The authors appreciate the support of Zhejiang Zheneng Technology and Environment Group Co.,Ltd’s project(No.TD-KJ-23-005:Methanation of carbon monoxide coupled with in-situ formed hydrogen in a low-temperature SOEC reactor).
文摘Proton ceramic fuel cell efficiently converts chemical energy into electrical energy,representing a pivotal component of future energy systems.However,its current performance is hindered by limitations in cathode and electrolyte materials,thereby impeding commercialization.Anion doping emerges as a promising strategy to enhance the electrochemical efficiency of perovskite-based cathodes and electrolytes.However,integrating this approach within a single-cell structure still requires further research.In this study,F-doped perovskite oxides BaCo_(0.4)Fe_(0.4)Zr_(0.1)Y_(0.1)O_(2.9-δ)F_(0.1)(BCFZYF)and BaZr_(0.1)Ce_(0.7)Y_(0.1)Yb_(0.1)O_(2.9-δ)F_(0.1)(BZCYYbF)were synthesized for use as the cathode and electrolyte,respectively,in proton ceramic fuel cells.Our findings demonstrate that F-doped perovskite oxides exhibit superior electrochemical performance and enhanced structural stability.Furthermore,doping both electrodes and electrolytes with F ions improves their interfacial compatibility.The cell configuration BCFZYF|BZCYYbF|Ni-BZCYYbF achieved a peak power density of 998 mW·cm^(−2)at 650℃using H_(2)as fuel,and it maintained stable operation for over 400 h at 550℃with a current density of 400 mA·cm^(−2).This research underscores an effective strategy for enhancing the performance and durability of proton ceramic fuel cells.
基金supported by the National Natural Science Foundation of China(Nos.52100087,52170079,U20A20322)Science and Technology Development Program of Jilin Province,China(Nos.20220508100RC,20230402035GH).
文摘Rational tuning of crystallographic surface and metal doping were effective to enhance the catalytic performance of metal organic frameworks,but limited work has been explored for achieving modulation of crystal facets and metal doping in a single system.MIL-68(In)was promising for photocatalytic applications due to its low toxicity and excellent photoresponsivity.However,its catalytic activity was constrained by severe carrier recombination and a lack of active sites.Herein,increased(001)facet ratio and active sites exposure were simultaneously realized by cobalt doping in MIL-68(In)through a one-pot solvothermal strategy.Optimized MIL-68(In/Co)-2.5 exhibited remarkable catalytic performance in comparison with pristine MIL-68(In)and other MIL-68(In/Co).The reaction kinetic constant and degradation efficiency of MIL-68(In/Co)were approximately twice and 17%higher than the pristine MIL-68(In)in 36 min reaction,respectively.Density functional theory calculations revealed that Co dopant could modulate the orientation of MIL-68(In)facets,facilitate the exchange of electrons and reduce the adsorption energy of peroxymonosulfate(PMS).This work provides a novel pathway for improvement of In-based MOFs in PMS/vis system,it also promotes the profound comprehension of the correlation between crystal facet regulation and catalytic activation in the PMS/vis system.
