Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled t...Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled thermomechanical fields remains insufficiently understood.In this study,transmission and scanning electron microscopy were employed to observe dislocation structures and grain boundary heterogeneities in processed aluminum alloys,suggesting stress concentrations and microstructural inhomogeneities associated with vacancy accumulation.To complement these observations,first-principles calculations and molecular dynamics simulations were conducted for seven single-vacancy configurations in face-centered cubic aluminum.The stress response,total energy,density of states(DOS),and differential charge density were examined under varying compressive strain(ε=0–0.1)and temperature(0–600 K).The results indicate that face-centered vacancies tend to reduce mechanical strength and perturb electronic states near the Fermi level,whereas corner and edge vacancies appear to have weaker effects.Elevated temperatures may partially restore electronic uniformity through thermal excitation.Overall,these findings suggest that vacancy position exerts a critical but position-dependent influence on coupled structure-property relationships,offering theoretical insights and preliminary experimental support for defect-engineered aluminum alloy design.展开更多
Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hin...Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.展开更多
Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting...Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting the reaction.During the reaction,the presence of oxygen vacancies can extract oxygen from NO,thereby facilitating the cleavage of NO on the catalyst surface.Thus,the formation of oxygen vacancies is key to accelerating the CO-SCR reaction,with different types of oxygen vacancies being more conducive to their generation.In this study,Rh/CeCuO_(x) catalysts were synthesized using the co-crystallization and impregnation methods,and asymmetric oxygen vacancies were induced through hydrogen thermal treatment.This structuralmodification was aimed at regulating the behavior of NO on the catalyst surface.The Rh/Ce0.95Cu0.05O_(x)-H_(2) catalyst exhibited the best performance in CO-SCR,achieving above 90%NO conversion at 162℃.Various characterization techniques showed that the H_(2) treatment effectively reduced some of the CuO and Rh_(2)O_(3),creating asymmetric oxygen vacancies that accelerated the cleavage of NO on the catalyst surface,rather than forming difficult-to-decompose nitrates.This study offers a novel approach to constructing oxygen vacancies in new CO-SCR catalysts.展开更多
Antibiotics and heavy metals usually co-exist in wastewater and pose serious environmental hazards.Herein,a series of VMo-BMO/O_(v)-BOB S-scheme heterojunctions with double vacancy(Mo vacancy and photoexcited O vacanc...Antibiotics and heavy metals usually co-exist in wastewater and pose serious environmental hazards.Herein,a series of VMo-BMO/O_(v)-BOB S-scheme heterojunctions with double vacancy(Mo vacancy and photoexcited O vacancy)were constructed via an electrostatic assembly method.The removal efficiency of Cr(VI)and tetracycline(TC)over VMo-BMO/O_(v)-BOB-0.3 was 2.47 and 1.13 times than that of a single system,respectively.In-situ EPR demonstrated that the surface O vacancies could be generated under LED light irradiation.These photoexcited O vacancies(P-O_(v))enabled VMo-BMO/O_(v)-BOB composites still exhibit satisfactory activity after five successive cycles and an amplified Fermi level gap.The enhancement could be attributed to the enhanced internal electric field and double-vacancy-induced polarization.Additionally,the density functional theory calculation results suggested that double vacancy induced polarization electric field increases the dipole moment,which was conducive to rapid electron transport.Photoluminescence and time-resolved photoluminescence analysis demonstrated that the introduction of S-scheme heterojunction and double vacancy promoted charge transfer and prolonged the lifetime of carriers.Degradation intermediates and toxicity of products were evaluated.In conclusion,a possible mechanism based on VMo-BMO/O_(v)-BOB S-scheme heterojunction in the simultaneous removal of Cr(VI)and TC was proposed.展开更多
The typical wastewater treatment is focused on the photocatalytic efficiency in the degradation of organic pollutants,with little attention to the involved selectivity which may correlate with toxicant residues.Herein...The typical wastewater treatment is focused on the photocatalytic efficiency in the degradation of organic pollutants,with little attention to the involved selectivity which may correlate with toxicant residues.Herein,an electron localization strategy for specific O2 adsorption/activation enabled by photothermal/pyroelectric effect and in situ constructed active centers of single-atom Co and oxygen vacancy(Co-O_(V))on the Co/BiOCl-O_(V)photocatalyst was developed for photocatalytic degradation of glyphosate(GLP)wastewater of high performance/selectivity.Under full-spectrum-light irradiation,a high GLP degradation rate of 99.8%with over 90%C-P bond-breaking selectivity was achieved within 2 h,while effectively circumventing toxicant residues such as aminomethylphosphonic acid(AMPA).X-ray absorption spectroscopy and relevant characterizations expounded the tailored anchoring of Co single atoms onto the BiOCl-O_(V)carrier and photothermal/pyroelectric effect.The oriented formation of more•O_(2)^(−)on Co/BiOCl-O_(V)could be achieved with the Co-O_(V)coupled center that had excellent O2 adsorption/activation capacity,as demonstrated by quantum calculations.The formed unique Co-O_(V)active sites could largely decrease the C-P bond-breaking energy barrier,thus greatly improving the selectivity toward the initial C-P bond scission and the activity in subsequent conversion steps in the directional photocatalytic degradation of GLP.The electron localization strategy by in situ constructing the coupled active centers provides an efficient scheme and new insights for the low-toxic photodegradation of organic pollutants containing C-X bonds.展开更多
Solid-state precipitation is an effective strategy for tuning the mechanical and functional properties of ad-vanced alloys.Structure design and modification necessitate good knowledge of the kinetic evolution of preci...Solid-state precipitation is an effective strategy for tuning the mechanical and functional properties of ad-vanced alloys.Structure design and modification necessitate good knowledge of the kinetic evolution of precipitates during fabrication,which is strongly correlated with defect concentration.For Fe-Ga alloys,giant magnetostriction can be induced by the precipitation of the nanoscale tetragonal L60 phase.By introducing quenched-in vacancies,we significantly enhance the magnetostriction of the aged Fe81Ga19 polycrystalline alloys to~305 ppm,which is close to the level of single crystals.Although vacancies were found to facilitate the generation of the L60 phase,their impact on the precipitation mechanism and kinetics has yet to be revealed.This study combined transmission electron microscopy(TEM)and time-resolved small-angle neutron scattering(SANS)to investigate the precipitation of the L60 phase during the isothermal aging at 350 and 400℃,respectively.The evolution of L60 nanophase in morphology and number density in as-cast(AC)and liquid nitrogen quenched(LN)Fe81Ga19 alloys with aging time were quantitatively compared.Interestingly,the nucleation of the L60 phase proceeds progressively in AC while suddenly in LN specimens,indicating the homogenous to heterogeneous mechanism switching in-duced by concentrated vacancies.Moreover,excess vacancies can change the shape of nanoprecipitates and significantly accelerate the growth and coarsening kinetics.The magnetostrictive coefficient is opti-mized when the size(long-axis)of L60 precipitates lies between 100 and 110Åwith a number density between 3.2-4.3×10-7Å-3.Insight from this study validates the feasibility of achieving high magnetoe-lastic properties through precise manipulation of the nanostructure.展开更多
The therapeutic efficacy of cuproptosis,ferroptosis,and apoptosis is hindered by inadequate intracellular copper and iron levels,hypoxia,and elevated glutathione(GSH)expression in tumor cells.Thermoelectric technology...The therapeutic efficacy of cuproptosis,ferroptosis,and apoptosis is hindered by inadequate intracellular copper and iron levels,hypoxia,and elevated glutathione(GSH)expression in tumor cells.Thermoelectric technology is an emerging frontier in medical therapy that aims to achieve efficient thermal and electrical transport characteristics within a narrow thermal range for biological systems.Here,we systematically constructed biodegradable Cu_(2)MnS_(3-x)-PEG/glucose oxidase(MCPG)with sulfur vacancies(S_(V))using photothermoelectric catalysis(PTEC),photothermal-enhanced enzyme catalysis,and starvation therapy.This triggers GSH consumption and disrupts intracellular redox homeostasis,leading to immunogenic cell death.Under 1064 nm laser irradiation,MCPG enriched with S_(V),owing to doping,generates a local temperature gradient that activates PTEC and produces toxic reactive oxygen species(ROS).Hydroxyl radicals and oxygen are generated through peroxide and catalase-like processes.Increased oxygen levels alleviate tumor hypoxia,whereas hydrogen peroxide production from glycometabolism provides sufficient ROS for a cascade catalytic reaction,establishing a self-reinforcing positive mechanism.Density functional theory calculations demonstrated that vacancy defects effectively enhanced enzyme catalytic activity.Multimodal imaging-guided synergistic therapy not only damages tumor cells,but also elicits an antitumor immune response to inhibit tumor metastasis.This study offers novel insights into the cuproptosis/ferroptosis/apoptosis pathways of Cu-based PTEC nanozymes.展开更多
The authors regret<During the submission process,Hongxiang Zhang and Honggen Peng served as the first and the second corresponding author,respectively.The original manuscript submitted for this paper also listed tw...The authors regret<During the submission process,Hongxiang Zhang and Honggen Peng served as the first and the second corresponding author,respectively.The original manuscript submitted for this paper also listed two co-corresponding authors(Hongxiang Zhang and Honggen Peng).But the corresponding author of Honggen Peng was omitted in the final published manuscript.So,we apply to designate Honggen Peng(penghonggen@ncu.edu.cn)as the second co-corresponding author and the corresponding unit is“a,b">.展开更多
The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work ...The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work demonstrates a strategy to constructed ethylene glycol(EG)well-coupled S-scheme heterojunction of NiFe_(2)O_(4-x)/NiS with oxygen vacancy(VO)-modified to efficiently achieve pollutant removal by activating PMS through photoexcitation,a 99%PMS decomposition efficiency is achieved.Photoassisted Kelvin probe force microscopy and in-situ electron spin resonance verify the establishment of a charge-transfer pathway consistent in NiFe_(2)O_(4-x)/NiS with an S-scheme heterojunction,which dramatically provides abundant active sites and distinct charge transport pathway for organic pollutant oxidation.The S-scheme NiFe_(2)O_(4-x)/NiS heterojunction in the photo-Fenton-like system exhibited significantly enhanced degradation rate(0.15 min^(-1))at a low PMS dosage of 0.1 g/L,which is 19 times greater than that of the pristine NiS(0.0077 min^(-1)).Density functional theory calculations confirmed that VO in NiFe_(2)O_(4-x)/NiS efficiently promoted PMS adsorption and lowered the energy barrier for electron transfer.Moreover,in-situ experiments and experimental evidence offer mechanistic insights into the PMS activation through photoexcitation,unraveling a dual-pathway activation mechanism involving reduction and oxidation processes over NiFe_(2)O_(4-x)/NiS during the reaction.This work emphasizes the potential of vacancy engineering synergistic S-scheme heterojunction in developing efficient catalysts for regulating PMS activation,providing a promising solution the cost-effective and efficient treatment of organic wastewater.展开更多
The synergy of metal/oxygen vacancy(O_(v))pairs is critical in catalyzing activation of C-H,C=C,and C-O bonds.However,gaining fundamental understanding on spatial distance of metallic and O_(v)sites on catalyst surfac...The synergy of metal/oxygen vacancy(O_(v))pairs is critical in catalyzing activation of C-H,C=C,and C-O bonds.However,gaining fundamental understanding on spatial distance of metallic and O_(v)sites on catalyst surface would lead to unexpected chemoselectivity toward important and challenging reactions.In this work,we have proposed and validated unique Ni-O-Ce-O_(v)enriched Ni/CeO_(2)catalysts prepared by a deposition-precipitation method,for the transfer hydrogenation of lignin-derived guaiacol toward cyclohexanol rather than benzene derivatives.The counter-intuitively designed high Ni loading Ni_(2)0/CeO_(2)catalyst(20 wt%Ni content)displays a distance of 0.5 nm for Ni/O_(v)pairs with a remarkable activity(TOF:166.5 h^(-1))and 90%+selectivity for C_(Ar)=C_(Ar)bond saturation,outperforming better metal-dispersed Ni_(5)/CeO_(2)catalyst with limited presence of Ni-O-Ce-O_(v)sites.The high hydrogenation activity against hydrogenolysis reactions on Ni_(2)0/CeO_(2)catalyst is attributed to tunable Ni/O_(v)distances,which constrain the cleavage of CAr-OH bond and deep deoxygenation.Such spatial distribution effect has also facilitated tandem dehydrogenation(O-H bond cleavage)and hydrogenation(C_(Ar)=C_(Ar)hydrogenation)reactions,leading to cyclohexanol as the target product in the absence of externally added H_(2).Insights into spatial distribution of O_(v)sites open an alternative perspective in designing efficient catalysts toward producing value-added cyclic oxygenates through upgrading of lignin compounds.展开更多
In the past decade,dry reforming of methane(DRM)has garnered increasing interest as it converts CH_(4)and CO_(2),two typical greenhouse gases,into synthesis gas(H_(2)and CO)for the production of high-value-added chemi...In the past decade,dry reforming of methane(DRM)has garnered increasing interest as it converts CH_(4)and CO_(2),two typical greenhouse gases,into synthesis gas(H_(2)and CO)for the production of high-value-added chemicals and fuels.Nickel-based DRM catalysts,renowned for their high activity and low cost,however,encounter challenges such as severe deactivation from sintering and carbon deposition.Herein,a surrounded NiO@NiAlO precursor derived from Ni(OH)_(2)nanosheets was modified at both the core and shell interfaces with MgO via wet impregnation.The obtained 0.8MgO^(WI)/Ni@NiAlO catalyst achieved a high CH_(4)reaction rate of~177 mmol gNi^(-1)min^(-1)and remained stable for 50 h at 600℃without coke formation.In sharp contrast,other Mg-doped catalysts(MgO modified the core or shell interfaces)and the catalyst without Mg-doping deactivated within 10 h due to coking or Ni particle sintering.The Ni/MgNiO_(2)interfaces and abundant oxygen vacancies(O_(v))generated by Mg-doping contributed to the outstanding resistance to sintering&coking as well as the superior activity and stability of the 0.8MgO^(WI)/Ni@NiAlO catalyst.In-situ investigation further unveiled the reaction mechanism:the activation of CO_(2)via adsorption on O_(v)generates active oxygen species(O^(*)),which reacts with CH_(x)^(*)intermediates formed by the dissociation of CH_(4)on Ni sites,yielding CO and H_(2).This work not only fabricates coke-free and high-stability Ni-based DRM catalysts via interface engineering but also provides insights and a new strategy for the design of high-efficiency and stable catalysts for DRM.展开更多
materials,despite its intensive application in Li/Na-ion batteries.The existing mechanisms of AVE's effects mainly focus on charge transfer but fail to clarify other critical issues.Here,we propose a new insight i...materials,despite its intensive application in Li/Na-ion batteries.The existing mechanisms of AVE's effects mainly focus on charge transfer but fail to clarify other critical issues.Here,we propose a new insight into AVE's effect on K-ion storage by introducing Te vacancies into a representative conversion-type NiTe.In addition to existing mechanisms,we demonstrate Te vacancies play three other unprecedented roles.(1)Te vacancies minimize the intrinsic volume strain from 15%to 6%,significantly suppressing anode pulverization and element dissolution.(2)Te vacancies induce the in-situ formation of a thin yet robust KF-based inorganic-rich solid electrolyte interphase,further accommodating volume strain and element dissolution.(3)Te vacancies reduce Ni-Te bond lengths and promote K-ion diffusion by modulating local atomic structure.Therefore,NiTe_(1-x)delivers an outstanding cycling performance(229.5 mAh g1 at 3.0 A g^(-1)for 1350 cycles)and rate capability(171.7 mAh g^(-1)at 5.0 A g^(-1)1).Furthermore,NiTe_(1-x)-based full cells showcase a remarkable energy density of 200.4 Wh kg^(-1).This work comprehensively elucidates the AVE's effects on alkali-ion storage,promoting the development of advanced conversion-type anode materials for practical applications.展开更多
A hydrogen spillover-bridged water dissociation/hydrogen formation could concurrently promote Volmer/Tafel process and improve the efficiency of hydrogen evolution reaction(HER)under alkaline conditions.However,it is ...A hydrogen spillover-bridged water dissociation/hydrogen formation could concurrently promote Volmer/Tafel process and improve the efficiency of hydrogen evolution reaction(HER)under alkaline conditions.However,it is still challenging to promote occurrence of hydrogen spillover for the large interfacial transport barriers of H_(2)O and hydrogen on active sites.Herein,the strategy of energy barrier gradient to induce hydrogen spillover was proposed by constructing Ru nanoclusters coupled with single atom onto oxygen vacancy cerium dioxide(Ru/CeO_(2)-Ov-2).Density functional theory(DFT)calculations uncover that the adsorption/desorption of H2O occurs at the Ru clusters sites and then the dissociated H*spontaneously overflows from Ru clusters with high binding energy into the adjacent Ru single atom sites with low binding energy,which facilitate the hydrogen formation.Consequently,the synthesized Ru/CeO_(2)-Ov-2 exhibits a small overpotential of 41 mV at 10 mA cm^(-2)and good stability at 500 mA cm^(-2)for 100 h in alkaline seawater,which could be ascribed to the rapid hydrogen spillover and strong coupling interaction between Ru and CeO_(2)-O_(v).This work provides a novel insight that synthesizing cooperative sites with energy barrier gradient helps to promote hydrogen spillover and accelerate the Volmer/Tafel process of HER.展开更多
The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of th...The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of the C–C coupling reaction remains a significant obstacle in achieving both high activity and selectivity for C_(2+) production. In this study, we demonstrated the use of defect engineering to promote COER towards C_(2+) products by introducing single chlorine vacancy (SVCl) into two-dimensional (2D) non-noble transition metal dichlorides (TMCl_(2)). Density functional theory (DFT) calculations revealed that SVCl in TMCl_(2) exhibits low formation energies and high stability, ensuring its feasibility for synthesis and application in electrocatalysis. The introduction of three-coordinated, unsaturated metal sites substantially enhances the catalytic activity of TMCl_(2), facilitating effective CO activation. Notably, SVCl-engineered CoCl_(2) and NiCl_(2) nanosheets exhibit superior performance in COER, with SVCl@CoCl_(2) showing catalytic activity for ethanol and propanol production, and SVCl@NiCl_(2) favoring ethanol production due to a lower limiting potential and smaller kinetic barrier for C–C coupling. Consequently, defective 2D TMCl_(2) nanosheets represent a highly promising platform for converting CO into value-added C_(2+) products, warranting further experimental investigation into defect engineering for CO conversion.展开更多
Transition metal-based electrocatalysts are a promising alternative to noble metal catalysts for electrochemical upgrading of biomass-derived 5-hydroxymethylfurfural(HMF)into high-value 2,5-furandicarboxylic acid(FDCA...Transition metal-based electrocatalysts are a promising alternative to noble metal catalysts for electrochemical upgrading of biomass-derived 5-hydroxymethylfurfural(HMF)into high-value 2,5-furandicarboxylic acid(FDCA).However,the rational design of efficient electrocatalysts with precisely tailored structure-activity correlations remains a critical challenge.Herein,we report a hierarchically structured self-supporting electrode(Vo-NiCo(OH)_(2)-NF)synthesized through in situ electrochemical reconstruction of NiCo-Prussian blue analogue(NiCo-PBA)precursor,in which oxygen vacancy(Vo)-rich Co-doped Ni(OH)_(2)nanosheet arrays are vertically aligned on nickel foam(NF),creating an interconnected conductive network.When evaluated for the HMF oxidation reaction(HMFOR),Vo-NiCo(OH)_(2)-NF exhibits exceptional electrochemical performance,achieving near-complete HMF conversion(99%),ultrahigh FDCA Faradaic efficiency(97.5%),and remarkable product yield(96.2%)at 1.45 V,outperforming conventional Co-doped Ni(OH)_(2)(NiCo(OH)_(2)-NF)and pristine Ni(OH)_(2)(Ni(OH)_(2)-NF)electrodes.By combining in situ spectroscopic characterization and theoretical calculations,we elucidate that the synergistic effects of Co-doping and oxygen vacancy engineering effectively modulate the electronic structure of Ni active centers,favor the formation of high-valent Ni^(3+)species,and optimize HMF adsorption,thereby improving the HMFOR performance.This work provides valuable mechanistic insights for catalyst design and may inspire the development of advanced transition metal-based electrodes for efficient biomass conversion systems.展开更多
Correction to:Rare Met.https://doi.org/10.1007/s12598-021-01864-4 In the original publication,the affiliation of the 5th author(Corresponding author)was published incorrectly.The correct affiliation is given in this C...Correction to:Rare Met.https://doi.org/10.1007/s12598-021-01864-4 In the original publication,the affiliation of the 5th author(Corresponding author)was published incorrectly.The correct affiliation is given in this Correction.The original publication has been corrected.展开更多
Ammonia is essential for agriculture and,as a next-generation carbon-free fuel,typically produced through the Haber-Bosch method.This process requires high temperature and pressure,leading to significant energy consum...Ammonia is essential for agriculture and,as a next-generation carbon-free fuel,typically produced through the Haber-Bosch method.This process requires high temperature and pressure,leading to significant energy consumption and greenhouse gas emissions.Therefore,achieving ammonia synthesis under milder conditions has been a long-standing goal.In this study,we design and synthesize a series of CeO_(2)-modified Fe/carbon-based catalysts with varying amounts of CeO_(2)(Ce_(x)Fe_(y)/C).The catalyst Ce_(2)Fe_(5)/C demonstrates an ammonia yield rate of 3.5 mmol/(g·h),which is 44 times greater than that of Fe/C and 8 times greater than that of commercial Fe-based catalysts at 300℃and 1 MPa.Temperature-programmed desorption experiments show that Ce_(2)Fe_(5)/C has enhanced nitrogen adsorption capabilities.Multiple analyses confirm that the CeO_(2)in Ce_(2)Fe_(5)/C is rich in oxygen vacancies,which can provide electrons to Fe,facilitating nitrogen adsorption,dissociation,and activity in low-temperature ammonia synthesis.展开更多
This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A compar...This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A comparative exploration of TEA gas sensing characterization for different Co_(3)O_(4)-based sensors is conducted systematically.The result shows that the sensor based on the NiZn–Co_(3)O_(4)HCSS displays the highest sensing response of 42.5 at a working temperature of 180°C.In particular,the Ni Zn–Co_(3)O_(4)HCSS device possesses a fast responserecovery speed,excellent anti-humidity and outstanding long-term stability of up to 40 days to TEA gas.The improved TEA gas sensing property can be attributed to the intriguing hierarchical core–shell architecture and abundant oxygen vacancy induced by NiZn co-doping.Moreover,to study the sensing mechanism in detail,the adsorption behavior and charge transfer phenomenon between OV–NiZn–Co_(3)O_(4)(110)and TEA molecule is carried out by the density functional theory(DFT).This work demonstrates an outstanding performance of Ni and Zn co-doped hierarchical core–shell Co_(3)O_(4)in TEA detection by combining theoretical and experimental investigations into mechanisms for optimized TEA gas molecule sensing.展开更多
Single negatively charged nitrogen vacancy(NV-)centers in diamond have emerged as promising platforms for quantum information science,where long coherence times are essential for advancing quantum technologies.However...Single negatively charged nitrogen vacancy(NV-)centers in diamond have emerged as promising platforms for quantum information science,where long coherence times are essential for advancing quantum technologies.However,traditional fabrication methods often introduce lattice damage during the irradiation process used to create vacancies,significantly impairing the spin coherence properties of NV-centers.展开更多
Developing cost-effective and high-activity catalysts for the methanolysis of ammonia borane(AB)has attracted great attention in the field of hydrogen energy recently.Besides the modification of the electronic structu...Developing cost-effective and high-activity catalysts for the methanolysis of ammonia borane(AB)has attracted great attention in the field of hydrogen energy recently.Besides the modification of the electronic structure of the catalysts,external factors such as visible light irradiation can improve the efficiency of hydrogen production as well.In the present study,a Z-scheme heterostructured VO-Cu_(0.5)Ni_(0.5)O catalysts were constructed by introducing a plenteous phase interface and oxygen vacancy(Vo).The catalytic activity of as-prepared VO-Cu_(0.5)Ni_(0.5)O toward AB methanolysis has been improved dramatically with the assistance of visible light irradiation.The turnover frequency(TOF)under visible light irradiation was measured to be 29_(mol)H_(2)·mol_(cat.)^(-1)·min^(-1),which is 1.4 times larger than the TOF in the absence of visible light.Systematic characterization experiments and density functional theory(DFT)calculations were conducted to unveil the causation of enhanced catalytic activity.The results demonstrated that the enhancement of the catalytic activity of VO-Cu_(0.5)Ni_(0.5)O originated from the electronic structure modification induced by the formation of heterojunctions,the introduction of oxygen vacancies,and the assistance of visible light cooperatively.The formation of heterojunction and the introduction of oxygen vacancies provoked the upshift of the d-band center;while the visible light irradiation induced the photogenerated electrons to transfer from Cu to Ni sites at the interface.Such electron structure modulation is beneficial for the construction of abundant active sites,thereby enhancing the adsorption of methanol on the Ni sites,which is considered as the rate-determine step for the methanolysis of AB.The strong interaction between Ni and O weakened the O-H bond of methanol,accelerating the methanolysis of AB.These results demonstrate the utilization of combined heterojunction,oxygen vacancy,and visible light to explore highly active AB methanolysis catalysts,which should shed light on the exploration of more effective catalysts for AB methanolysis.展开更多
基金supported by the Research Project on Strengthening the Construction of an Important Ecological Security Barrier in Northern China by Higher Education Institutions in the Inner Mongolia Autonomous Region(STAQZX202313)the Inner Mongolia Autonomous Region Education Science‘14th Five-Year Plan’2024 Annual Research Project(NGJGH2024635).
文摘Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled thermomechanical fields remains insufficiently understood.In this study,transmission and scanning electron microscopy were employed to observe dislocation structures and grain boundary heterogeneities in processed aluminum alloys,suggesting stress concentrations and microstructural inhomogeneities associated with vacancy accumulation.To complement these observations,first-principles calculations and molecular dynamics simulations were conducted for seven single-vacancy configurations in face-centered cubic aluminum.The stress response,total energy,density of states(DOS),and differential charge density were examined under varying compressive strain(ε=0–0.1)and temperature(0–600 K).The results indicate that face-centered vacancies tend to reduce mechanical strength and perturb electronic states near the Fermi level,whereas corner and edge vacancies appear to have weaker effects.Elevated temperatures may partially restore electronic uniformity through thermal excitation.Overall,these findings suggest that vacancy position exerts a critical but position-dependent influence on coupled structure-property relationships,offering theoretical insights and preliminary experimental support for defect-engineered aluminum alloy design.
文摘Rectifying circuit,as a crucial component for converting alternating current into direct current,plays a pivotal role in energy harvesting microsystems.Traditional silicon-based or germanium-based rectifier diodes hinder system integration due to their specific manufacturing processes.Conversely,metal oxide diodes,with their simple fabrication techniques,offer advantages for system integration.The oxygen vacancy defect of oxide semiconductor will greatly affect the electrical performance of the device,so the performance of the diode can be effectively controlled by adjusting the oxygen vacancy concentration.This study centers on optimizing the performance of diodes by modulating the oxygen vacancy concentration within InGaZnO films through control of oxygen flows during the sputtering process.Experimental results demonstrate that the diode exhibits a forward current density of 43.82 A·cm^(−2),with a rectification ratio of 6.94×10^(4),efficiently rectifying input sine signals with 1 kHz frequency and 5 V magnitude.These results demonstrate its potential in energy conversion and management.By adjusting the oxygen vacancy,a methodology is provided for optimizing the performance of rectifying diodes.
基金supported by the support of the National Natural Science Foundation of China(Nos.22072141,22176185 and 52304429)the National Key Research and Development Program of China(Nos.2022YFB3504200,2021YFB3501900)+4 种基金the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars(No.20232ACB213004)Jiangxi Provincial Key Research and Development Program(No.20232BBG70012)Jiangxi Provincial Natural Science Foundation(No.20212BAB213032)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2018263)the Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(No.E355C001).
文摘Selective catalytic reduction of NO_(x) with CO(CO-SCR)is a process that purifies both NO and CO pollutants through a catalytic reaction.Specifically,the cleavage of NO on the catalyst surface is crucial for promoting the reaction.During the reaction,the presence of oxygen vacancies can extract oxygen from NO,thereby facilitating the cleavage of NO on the catalyst surface.Thus,the formation of oxygen vacancies is key to accelerating the CO-SCR reaction,with different types of oxygen vacancies being more conducive to their generation.In this study,Rh/CeCuO_(x) catalysts were synthesized using the co-crystallization and impregnation methods,and asymmetric oxygen vacancies were induced through hydrogen thermal treatment.This structuralmodification was aimed at regulating the behavior of NO on the catalyst surface.The Rh/Ce0.95Cu0.05O_(x)-H_(2) catalyst exhibited the best performance in CO-SCR,achieving above 90%NO conversion at 162℃.Various characterization techniques showed that the H_(2) treatment effectively reduced some of the CuO and Rh_(2)O_(3),creating asymmetric oxygen vacancies that accelerated the cleavage of NO on the catalyst surface,rather than forming difficult-to-decompose nitrates.This study offers a novel approach to constructing oxygen vacancies in new CO-SCR catalysts.
文摘Antibiotics and heavy metals usually co-exist in wastewater and pose serious environmental hazards.Herein,a series of VMo-BMO/O_(v)-BOB S-scheme heterojunctions with double vacancy(Mo vacancy and photoexcited O vacancy)were constructed via an electrostatic assembly method.The removal efficiency of Cr(VI)and tetracycline(TC)over VMo-BMO/O_(v)-BOB-0.3 was 2.47 and 1.13 times than that of a single system,respectively.In-situ EPR demonstrated that the surface O vacancies could be generated under LED light irradiation.These photoexcited O vacancies(P-O_(v))enabled VMo-BMO/O_(v)-BOB composites still exhibit satisfactory activity after five successive cycles and an amplified Fermi level gap.The enhancement could be attributed to the enhanced internal electric field and double-vacancy-induced polarization.Additionally,the density functional theory calculation results suggested that double vacancy induced polarization electric field increases the dipole moment,which was conducive to rapid electron transport.Photoluminescence and time-resolved photoluminescence analysis demonstrated that the introduction of S-scheme heterojunction and double vacancy promoted charge transfer and prolonged the lifetime of carriers.Degradation intermediates and toxicity of products were evaluated.In conclusion,a possible mechanism based on VMo-BMO/O_(v)-BOB S-scheme heterojunction in the simultaneous removal of Cr(VI)and TC was proposed.
基金supported by the National Natural Science Foundation of China(No.22368014)Guizhou Provincial S&T Project(Nos.GCC[2023]011,ZK[2022]011)Guizhou Provincial Higher Education Institution Program(No.Qianjiaoji[2023]082).
文摘The typical wastewater treatment is focused on the photocatalytic efficiency in the degradation of organic pollutants,with little attention to the involved selectivity which may correlate with toxicant residues.Herein,an electron localization strategy for specific O2 adsorption/activation enabled by photothermal/pyroelectric effect and in situ constructed active centers of single-atom Co and oxygen vacancy(Co-O_(V))on the Co/BiOCl-O_(V)photocatalyst was developed for photocatalytic degradation of glyphosate(GLP)wastewater of high performance/selectivity.Under full-spectrum-light irradiation,a high GLP degradation rate of 99.8%with over 90%C-P bond-breaking selectivity was achieved within 2 h,while effectively circumventing toxicant residues such as aminomethylphosphonic acid(AMPA).X-ray absorption spectroscopy and relevant characterizations expounded the tailored anchoring of Co single atoms onto the BiOCl-O_(V)carrier and photothermal/pyroelectric effect.The oriented formation of more•O_(2)^(−)on Co/BiOCl-O_(V)could be achieved with the Co-O_(V)coupled center that had excellent O2 adsorption/activation capacity,as demonstrated by quantum calculations.The formed unique Co-O_(V)active sites could largely decrease the C-P bond-breaking energy barrier,thus greatly improving the selectivity toward the initial C-P bond scission and the activity in subsequent conversion steps in the directional photocatalytic degradation of GLP.The electron localization strategy by in situ constructing the coupled active centers provides an efficient scheme and new insights for the low-toxic photodegradation of organic pollutants containing C-X bonds.
基金supported by the National Natural Science Foundation of China(Grant No.12275154)the Guangdong Basic and Applied Basic Research Foundation,China(Project No.2021B1515140028)+1 种基金the Youth Innovation Promotion Association,CAS(No.2020010)the National Key Research and Development Program of China,grant number(Nos.2021YFA1600701 and 2021YFB3501201).
文摘Solid-state precipitation is an effective strategy for tuning the mechanical and functional properties of ad-vanced alloys.Structure design and modification necessitate good knowledge of the kinetic evolution of precipitates during fabrication,which is strongly correlated with defect concentration.For Fe-Ga alloys,giant magnetostriction can be induced by the precipitation of the nanoscale tetragonal L60 phase.By introducing quenched-in vacancies,we significantly enhance the magnetostriction of the aged Fe81Ga19 polycrystalline alloys to~305 ppm,which is close to the level of single crystals.Although vacancies were found to facilitate the generation of the L60 phase,their impact on the precipitation mechanism and kinetics has yet to be revealed.This study combined transmission electron microscopy(TEM)and time-resolved small-angle neutron scattering(SANS)to investigate the precipitation of the L60 phase during the isothermal aging at 350 and 400℃,respectively.The evolution of L60 nanophase in morphology and number density in as-cast(AC)and liquid nitrogen quenched(LN)Fe81Ga19 alloys with aging time were quantitatively compared.Interestingly,the nucleation of the L60 phase proceeds progressively in AC while suddenly in LN specimens,indicating the homogenous to heterogeneous mechanism switching in-duced by concentrated vacancies.Moreover,excess vacancies can change the shape of nanoprecipitates and significantly accelerate the growth and coarsening kinetics.The magnetostrictive coefficient is opti-mized when the size(long-axis)of L60 precipitates lies between 100 and 110Åwith a number density between 3.2-4.3×10-7Å-3.Insight from this study validates the feasibility of achieving high magnetoe-lastic properties through precise manipulation of the nanostructure.
基金supported by the National Natural Science Foundation of China(NSFC 52002091,U22A20347,and 52102344)Heilongjiang Natural Science Foundation Project of Outstanding Youth Project(YQ2023B005)+1 种基金China Postdoctoral Science Foundation(2023T160154)the Fundamental Research Funds for the Central Universities。
文摘The therapeutic efficacy of cuproptosis,ferroptosis,and apoptosis is hindered by inadequate intracellular copper and iron levels,hypoxia,and elevated glutathione(GSH)expression in tumor cells.Thermoelectric technology is an emerging frontier in medical therapy that aims to achieve efficient thermal and electrical transport characteristics within a narrow thermal range for biological systems.Here,we systematically constructed biodegradable Cu_(2)MnS_(3-x)-PEG/glucose oxidase(MCPG)with sulfur vacancies(S_(V))using photothermoelectric catalysis(PTEC),photothermal-enhanced enzyme catalysis,and starvation therapy.This triggers GSH consumption and disrupts intracellular redox homeostasis,leading to immunogenic cell death.Under 1064 nm laser irradiation,MCPG enriched with S_(V),owing to doping,generates a local temperature gradient that activates PTEC and produces toxic reactive oxygen species(ROS).Hydroxyl radicals and oxygen are generated through peroxide and catalase-like processes.Increased oxygen levels alleviate tumor hypoxia,whereas hydrogen peroxide production from glycometabolism provides sufficient ROS for a cascade catalytic reaction,establishing a self-reinforcing positive mechanism.Density functional theory calculations demonstrated that vacancy defects effectively enhanced enzyme catalytic activity.Multimodal imaging-guided synergistic therapy not only damages tumor cells,but also elicits an antitumor immune response to inhibit tumor metastasis.This study offers novel insights into the cuproptosis/ferroptosis/apoptosis pathways of Cu-based PTEC nanozymes.
文摘The authors regret<During the submission process,Hongxiang Zhang and Honggen Peng served as the first and the second corresponding author,respectively.The original manuscript submitted for this paper also listed two co-corresponding authors(Hongxiang Zhang and Honggen Peng).But the corresponding author of Honggen Peng was omitted in the final published manuscript.So,we apply to designate Honggen Peng(penghonggen@ncu.edu.cn)as the second co-corresponding author and the corresponding unit is“a,b">.
文摘The regulation of peroxymonosulfate(PMS)activation by constructing oxygen vacancy and heterogeneous interface catalytic is crucial towards the oxidation of refractory pollutants still remains a major hurdle.This work demonstrates a strategy to constructed ethylene glycol(EG)well-coupled S-scheme heterojunction of NiFe_(2)O_(4-x)/NiS with oxygen vacancy(VO)-modified to efficiently achieve pollutant removal by activating PMS through photoexcitation,a 99%PMS decomposition efficiency is achieved.Photoassisted Kelvin probe force microscopy and in-situ electron spin resonance verify the establishment of a charge-transfer pathway consistent in NiFe_(2)O_(4-x)/NiS with an S-scheme heterojunction,which dramatically provides abundant active sites and distinct charge transport pathway for organic pollutant oxidation.The S-scheme NiFe_(2)O_(4-x)/NiS heterojunction in the photo-Fenton-like system exhibited significantly enhanced degradation rate(0.15 min^(-1))at a low PMS dosage of 0.1 g/L,which is 19 times greater than that of the pristine NiS(0.0077 min^(-1)).Density functional theory calculations confirmed that VO in NiFe_(2)O_(4-x)/NiS efficiently promoted PMS adsorption and lowered the energy barrier for electron transfer.Moreover,in-situ experiments and experimental evidence offer mechanistic insights into the PMS activation through photoexcitation,unraveling a dual-pathway activation mechanism involving reduction and oxidation processes over NiFe_(2)O_(4-x)/NiS during the reaction.This work emphasizes the potential of vacancy engineering synergistic S-scheme heterojunction in developing efficient catalysts for regulating PMS activation,providing a promising solution the cost-effective and efficient treatment of organic wastewater.
基金supported by the National Natural Science Foundation of China(22078365,22478437)the Natural Science Foundation of Shandong Province(ZR2023MB076)。
文摘The synergy of metal/oxygen vacancy(O_(v))pairs is critical in catalyzing activation of C-H,C=C,and C-O bonds.However,gaining fundamental understanding on spatial distance of metallic and O_(v)sites on catalyst surface would lead to unexpected chemoselectivity toward important and challenging reactions.In this work,we have proposed and validated unique Ni-O-Ce-O_(v)enriched Ni/CeO_(2)catalysts prepared by a deposition-precipitation method,for the transfer hydrogenation of lignin-derived guaiacol toward cyclohexanol rather than benzene derivatives.The counter-intuitively designed high Ni loading Ni_(2)0/CeO_(2)catalyst(20 wt%Ni content)displays a distance of 0.5 nm for Ni/O_(v)pairs with a remarkable activity(TOF:166.5 h^(-1))and 90%+selectivity for C_(Ar)=C_(Ar)bond saturation,outperforming better metal-dispersed Ni_(5)/CeO_(2)catalyst with limited presence of Ni-O-Ce-O_(v)sites.The high hydrogenation activity against hydrogenolysis reactions on Ni_(2)0/CeO_(2)catalyst is attributed to tunable Ni/O_(v)distances,which constrain the cleavage of CAr-OH bond and deep deoxygenation.Such spatial distribution effect has also facilitated tandem dehydrogenation(O-H bond cleavage)and hydrogenation(C_(Ar)=C_(Ar)hydrogenation)reactions,leading to cyclohexanol as the target product in the absence of externally added H_(2).Insights into spatial distribution of O_(v)sites open an alternative perspective in designing efficient catalysts toward producing value-added cyclic oxygenates through upgrading of lignin compounds.
文摘In the past decade,dry reforming of methane(DRM)has garnered increasing interest as it converts CH_(4)and CO_(2),two typical greenhouse gases,into synthesis gas(H_(2)and CO)for the production of high-value-added chemicals and fuels.Nickel-based DRM catalysts,renowned for their high activity and low cost,however,encounter challenges such as severe deactivation from sintering and carbon deposition.Herein,a surrounded NiO@NiAlO precursor derived from Ni(OH)_(2)nanosheets was modified at both the core and shell interfaces with MgO via wet impregnation.The obtained 0.8MgO^(WI)/Ni@NiAlO catalyst achieved a high CH_(4)reaction rate of~177 mmol gNi^(-1)min^(-1)and remained stable for 50 h at 600℃without coke formation.In sharp contrast,other Mg-doped catalysts(MgO modified the core or shell interfaces)and the catalyst without Mg-doping deactivated within 10 h due to coking or Ni particle sintering.The Ni/MgNiO_(2)interfaces and abundant oxygen vacancies(O_(v))generated by Mg-doping contributed to the outstanding resistance to sintering&coking as well as the superior activity and stability of the 0.8MgO^(WI)/Ni@NiAlO catalyst.In-situ investigation further unveiled the reaction mechanism:the activation of CO_(2)via adsorption on O_(v)generates active oxygen species(O^(*)),which reacts with CH_(x)^(*)intermediates formed by the dissociation of CH_(4)on Ni sites,yielding CO and H_(2).This work not only fabricates coke-free and high-stability Ni-based DRM catalysts via interface engineering but also provides insights and a new strategy for the design of high-efficiency and stable catalysts for DRM.
基金support from the National Natural Science Foundation of China(No.U23A20574,52201242)the Natural Science Foundation of Jiangsu Province(No.BK20240179).
文摘materials,despite its intensive application in Li/Na-ion batteries.The existing mechanisms of AVE's effects mainly focus on charge transfer but fail to clarify other critical issues.Here,we propose a new insight into AVE's effect on K-ion storage by introducing Te vacancies into a representative conversion-type NiTe.In addition to existing mechanisms,we demonstrate Te vacancies play three other unprecedented roles.(1)Te vacancies minimize the intrinsic volume strain from 15%to 6%,significantly suppressing anode pulverization and element dissolution.(2)Te vacancies induce the in-situ formation of a thin yet robust KF-based inorganic-rich solid electrolyte interphase,further accommodating volume strain and element dissolution.(3)Te vacancies reduce Ni-Te bond lengths and promote K-ion diffusion by modulating local atomic structure.Therefore,NiTe_(1-x)delivers an outstanding cycling performance(229.5 mAh g1 at 3.0 A g^(-1)for 1350 cycles)and rate capability(171.7 mAh g^(-1)at 5.0 A g^(-1)1).Furthermore,NiTe_(1-x)-based full cells showcase a remarkable energy density of 200.4 Wh kg^(-1).This work comprehensively elucidates the AVE's effects on alkali-ion storage,promoting the development of advanced conversion-type anode materials for practical applications.
基金funding support from the National Natural Science Foundation of China(5237122722002068+8 种基金52272222,and 52072197)the Taishan Scholar Young Talent Program(tsqn201909114)the Shandong Province“Double-Hundred Talent Plan”(WST2020003)the Youth Innovation and Technology Foundation of Shandong Higher Education Institutions,China(2019KJC004)the Outstanding Youth Foundation of Shandong Province,China(ZR2019JQ14)the Major Basic Research Program of Natural Science Foundation of Shandong Province under Grant No.ZR2020ZD09the Major Scientific and Technological Innovation Project(2019JZZY020405)the University Youth Innovation Team of Shandong Province(202201010318)the Youth Innovation Team Development Program of Shandong Higher Education Institutions(2022KJ155)。
文摘A hydrogen spillover-bridged water dissociation/hydrogen formation could concurrently promote Volmer/Tafel process and improve the efficiency of hydrogen evolution reaction(HER)under alkaline conditions.However,it is still challenging to promote occurrence of hydrogen spillover for the large interfacial transport barriers of H_(2)O and hydrogen on active sites.Herein,the strategy of energy barrier gradient to induce hydrogen spillover was proposed by constructing Ru nanoclusters coupled with single atom onto oxygen vacancy cerium dioxide(Ru/CeO_(2)-Ov-2).Density functional theory(DFT)calculations uncover that the adsorption/desorption of H2O occurs at the Ru clusters sites and then the dissociated H*spontaneously overflows from Ru clusters with high binding energy into the adjacent Ru single atom sites with low binding energy,which facilitate the hydrogen formation.Consequently,the synthesized Ru/CeO_(2)-Ov-2 exhibits a small overpotential of 41 mV at 10 mA cm^(-2)and good stability at 500 mA cm^(-2)for 100 h in alkaline seawater,which could be ascribed to the rapid hydrogen spillover and strong coupling interaction between Ru and CeO_(2)-O_(v).This work provides a novel insight that synthesizing cooperative sites with energy barrier gradient helps to promote hydrogen spillover and accelerate the Volmer/Tafel process of HER.
基金financially supported by the International Partnership Program of the Chinese Academy of Sciences(No.172GJHZ2022010MI)the Natural Science Funds for Distinguished Young Scholars of Heilongjiang Province(No.JC2018004).
文摘The electrochemical reduction of carbon monoxide (COER) to high-value multicarbon (C_(2+)) products is an emerging strategy for artificial carbon fixation and renewable energy storage. However, the slow kinetics of the C–C coupling reaction remains a significant obstacle in achieving both high activity and selectivity for C_(2+) production. In this study, we demonstrated the use of defect engineering to promote COER towards C_(2+) products by introducing single chlorine vacancy (SVCl) into two-dimensional (2D) non-noble transition metal dichlorides (TMCl_(2)). Density functional theory (DFT) calculations revealed that SVCl in TMCl_(2) exhibits low formation energies and high stability, ensuring its feasibility for synthesis and application in electrocatalysis. The introduction of three-coordinated, unsaturated metal sites substantially enhances the catalytic activity of TMCl_(2), facilitating effective CO activation. Notably, SVCl-engineered CoCl_(2) and NiCl_(2) nanosheets exhibit superior performance in COER, with SVCl@CoCl_(2) showing catalytic activity for ethanol and propanol production, and SVCl@NiCl_(2) favoring ethanol production due to a lower limiting potential and smaller kinetic barrier for C–C coupling. Consequently, defective 2D TMCl_(2) nanosheets represent a highly promising platform for converting CO into value-added C_(2+) products, warranting further experimental investigation into defect engineering for CO conversion.
基金financial support of the National Natural Science Foundation of China(NSFC)(22372039 and 22305247)the Natural Science Foundation of Fujian Province of China(2021J06010)the Fuzhou University Testing Fund of Precious Apparatus(2025T022)。
文摘Transition metal-based electrocatalysts are a promising alternative to noble metal catalysts for electrochemical upgrading of biomass-derived 5-hydroxymethylfurfural(HMF)into high-value 2,5-furandicarboxylic acid(FDCA).However,the rational design of efficient electrocatalysts with precisely tailored structure-activity correlations remains a critical challenge.Herein,we report a hierarchically structured self-supporting electrode(Vo-NiCo(OH)_(2)-NF)synthesized through in situ electrochemical reconstruction of NiCo-Prussian blue analogue(NiCo-PBA)precursor,in which oxygen vacancy(Vo)-rich Co-doped Ni(OH)_(2)nanosheet arrays are vertically aligned on nickel foam(NF),creating an interconnected conductive network.When evaluated for the HMF oxidation reaction(HMFOR),Vo-NiCo(OH)_(2)-NF exhibits exceptional electrochemical performance,achieving near-complete HMF conversion(99%),ultrahigh FDCA Faradaic efficiency(97.5%),and remarkable product yield(96.2%)at 1.45 V,outperforming conventional Co-doped Ni(OH)_(2)(NiCo(OH)_(2)-NF)and pristine Ni(OH)_(2)(Ni(OH)_(2)-NF)electrodes.By combining in situ spectroscopic characterization and theoretical calculations,we elucidate that the synergistic effects of Co-doping and oxygen vacancy engineering effectively modulate the electronic structure of Ni active centers,favor the formation of high-valent Ni^(3+)species,and optimize HMF adsorption,thereby improving the HMFOR performance.This work provides valuable mechanistic insights for catalyst design and may inspire the development of advanced transition metal-based electrodes for efficient biomass conversion systems.
文摘Correction to:Rare Met.https://doi.org/10.1007/s12598-021-01864-4 In the original publication,the affiliation of the 5th author(Corresponding author)was published incorrectly.The correct affiliation is given in this Correction.The original publication has been corrected.
基金the Haihe Laboratory of Sus-tainable Chemical Transformations for financial support(No.24HHWCSS00009).
文摘Ammonia is essential for agriculture and,as a next-generation carbon-free fuel,typically produced through the Haber-Bosch method.This process requires high temperature and pressure,leading to significant energy consumption and greenhouse gas emissions.Therefore,achieving ammonia synthesis under milder conditions has been a long-standing goal.In this study,we design and synthesize a series of CeO_(2)-modified Fe/carbon-based catalysts with varying amounts of CeO_(2)(Ce_(x)Fe_(y)/C).The catalyst Ce_(2)Fe_(5)/C demonstrates an ammonia yield rate of 3.5 mmol/(g·h),which is 44 times greater than that of Fe/C and 8 times greater than that of commercial Fe-based catalysts at 300℃and 1 MPa.Temperature-programmed desorption experiments show that Ce_(2)Fe_(5)/C has enhanced nitrogen adsorption capabilities.Multiple analyses confirm that the CeO_(2)in Ce_(2)Fe_(5)/C is rich in oxygen vacancies,which can provide electrons to Fe,facilitating nitrogen adsorption,dissociation,and activity in low-temperature ammonia synthesis.
基金financially supported by the Doctoral Funding projects from Heze University(No.XY22BS07)
文摘This work presents a hierarchical yolk-shell NiZn-Co_(3)O_(4)sphere with abundant oxygen vacancy by utilizing structure optimization and composition regulation for efficient detection of triethylamine(TEA)gas.A comparative exploration of TEA gas sensing characterization for different Co_(3)O_(4)-based sensors is conducted systematically.The result shows that the sensor based on the NiZn–Co_(3)O_(4)HCSS displays the highest sensing response of 42.5 at a working temperature of 180°C.In particular,the Ni Zn–Co_(3)O_(4)HCSS device possesses a fast responserecovery speed,excellent anti-humidity and outstanding long-term stability of up to 40 days to TEA gas.The improved TEA gas sensing property can be attributed to the intriguing hierarchical core–shell architecture and abundant oxygen vacancy induced by NiZn co-doping.Moreover,to study the sensing mechanism in detail,the adsorption behavior and charge transfer phenomenon between OV–NiZn–Co_(3)O_(4)(110)and TEA molecule is carried out by the density functional theory(DFT).This work demonstrates an outstanding performance of Ni and Zn co-doped hierarchical core–shell Co_(3)O_(4)in TEA detection by combining theoretical and experimental investigations into mechanisms for optimized TEA gas molecule sensing.
基金supported by the National Natural Science Foundation of China(Grant Nos.112374012 and 11974208)Shandong Provincial Natural Science Foundation(Grant Nos.ZR2023JQ001 and tsqn202211128)。
文摘Single negatively charged nitrogen vacancy(NV-)centers in diamond have emerged as promising platforms for quantum information science,where long coherence times are essential for advancing quantum technologies.However,traditional fabrication methods often introduce lattice damage during the irradiation process used to create vacancies,significantly impairing the spin coherence properties of NV-centers.
基金supported the Natural Science Foundation of Guangdong Province(Nos.2022A1515140085,2022A1515111022 and 2022A1515110275)the Major and Special Project in the Field of Intelligent Manufacturing of the Universities in Guangdong Province(No.2020ZDZX2067)+2 种基金the Natural Science Foundation of Huizhou University(No.HZU202004)the Professorial and Doctoral Scientific Research Foundation of Huizhou University(No.2020JB046)the Open Project Program of Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices,Huizhou University(No.EFMDN2021004M).
文摘Developing cost-effective and high-activity catalysts for the methanolysis of ammonia borane(AB)has attracted great attention in the field of hydrogen energy recently.Besides the modification of the electronic structure of the catalysts,external factors such as visible light irradiation can improve the efficiency of hydrogen production as well.In the present study,a Z-scheme heterostructured VO-Cu_(0.5)Ni_(0.5)O catalysts were constructed by introducing a plenteous phase interface and oxygen vacancy(Vo).The catalytic activity of as-prepared VO-Cu_(0.5)Ni_(0.5)O toward AB methanolysis has been improved dramatically with the assistance of visible light irradiation.The turnover frequency(TOF)under visible light irradiation was measured to be 29_(mol)H_(2)·mol_(cat.)^(-1)·min^(-1),which is 1.4 times larger than the TOF in the absence of visible light.Systematic characterization experiments and density functional theory(DFT)calculations were conducted to unveil the causation of enhanced catalytic activity.The results demonstrated that the enhancement of the catalytic activity of VO-Cu_(0.5)Ni_(0.5)O originated from the electronic structure modification induced by the formation of heterojunctions,the introduction of oxygen vacancies,and the assistance of visible light cooperatively.The formation of heterojunction and the introduction of oxygen vacancies provoked the upshift of the d-band center;while the visible light irradiation induced the photogenerated electrons to transfer from Cu to Ni sites at the interface.Such electron structure modulation is beneficial for the construction of abundant active sites,thereby enhancing the adsorption of methanol on the Ni sites,which is considered as the rate-determine step for the methanolysis of AB.The strong interaction between Ni and O weakened the O-H bond of methanol,accelerating the methanolysis of AB.These results demonstrate the utilization of combined heterojunction,oxygen vacancy,and visible light to explore highly active AB methanolysis catalysts,which should shed light on the exploration of more effective catalysts for AB methanolysis.
