Regulation with nitrogen and oxygen co-doping on growth and properties of boron doped diamond films is studied by using laughing gas as dopant. As the concentration of laughing gas(N2O/C) increases from 0 to 10%, the ...Regulation with nitrogen and oxygen co-doping on growth and properties of boron doped diamond films is studied by using laughing gas as dopant. As the concentration of laughing gas(N2O/C) increases from 0 to 10%, the growth rate of diamond film decreases gradually, and the nitrogen-vacancy(NV) center luminescence intensity increases first and then weakens. The results show that oxygen in laughing gas has a strong inhibitory effect on formation of NV centers, and the inhibitory effect would be stronger as the concentration of laughing gas increases. As a result, the film growth rate and nitrogen-related compensation donor decrease, beneficial to increase the acceptor concentration(~3.2×10^(19)cm^(-3)) in the film. Moreover, it is found that the optimal regulation with the quality and electrical properties of boron doped diamond films could be realized by adding appropriate laughing gas, especially the hole mobility(~700cm^(2)/V·s), which is beneficial to the realization of high-quality boron doped diamond films and high-level optoelectronic device applications in the future.展开更多
Radiation induced reactive oxygen/nitrogen species (ROS/RNS) are reported to cause lung injuries such as pneumonitis and fibrosis which may be fatal at times. Current study is designed to analyse the radioprotective e...Radiation induced reactive oxygen/nitrogen species (ROS/RNS) are reported to cause lung injuries such as pneumonitis and fibrosis which may be fatal at times. Current study is designed to analyse the radioprotective efficacy of P. hexandrum active principles (G-002M) on lungs of mice exposed to high dose of gamma irradiation (7 Gy). Cellular profiles and inflammatory cell infiltrates of irradiated bronchoalveolar lavage fluid (BALF) have shown correlations with lung pathology. Cell counts were determined in BALF of control, 7 Gy radiation exposed and radiation with G-002M pretreated mice. ROS/Nitric Oxide (NO) production was measured by 2,7?dichlorodihydrofluorescein diacetate (DCF-DA) and diaminofluorescein diacetate (DAF-2DA) through microscopy and flow cytometry respectively. Immunostaining of inducible nitric oxide synthase (iNOS) in BALF cells and lung sections was also observed microscopically. iNOS ex- pression was observed in lungs by western blotting. BALF was also processed to estimate total protein, LDH, and phospholipids content. Catalase, reduced Glutathione (GSH), Glutathione reductase (GR) and lipid peroxidation were estimated in lung tissues. Pre-administration of G-002M significantly decreased radiation mediated neutrophils count in BALF of irradiated mice. ROS generation, iNOS expression, total protein, LDH and phospholipids were found less affected in G-002M pretreated group in comparison to radiation alone group. Radiation exposure to mice was found apparently leading to parenchymal fibrosis, an architectural distortion of the lung tissue with edema, infiltration of inflammatory blood cells with increased immunolabeling of iNOS. G-002M pretreatment significantly countered radiation mediated increased lipid peroxidation and decreased GR, catalase and GSH in mice. Current study demonstrates possible role of P. hexandrum (G-002M) in minimizing lung damage induced by radiation mediated ROS/RNS generation.展开更多
The Arno River Basin(Central Italy)is affected by a considerable anthropogenic pressure due to the presence of large cities and widespread industrial and agricultural practices.In this work,26 water samples from the A...The Arno River Basin(Central Italy)is affected by a considerable anthropogenic pressure due to the presence of large cities and widespread industrial and agricultural practices.In this work,26 water samples from the Arno River and its main tributaries were analyzed to assess the water pollution status.The geochemical composition of the Arno River changes from the source(dominated by a Ca-HCO_(3) facies)to the mouth(where a Na-Cl(SO4)chemistry prevails)with an increasing quality deterioration,as suggested by the Chemical Water Quality Index,due to anthropogenic contributions and seawater intrusion before flowing into the Ligurian Sea.The Ombrone and Usciana tributaries introduce anthropogenic pollutants into the Arno River,whilst Elsa tributary supplies significant contents of geogenic sulfate.The concentrations of dissolved nitrate and nitrite(up to 63 and 9 mg/L,respectively)and the respective isotopic values of𝛿15N and𝛿18O were also determined to understand origin and fate of the N-species in the Arno River Basin surface waters.The combined application of𝛿15N-NO_(3) and𝛿18O-NO_(3) and N-source apportionment modelling allowed the identification of soil organic nitrogen and sewage and domestic wastes as primary sources for dissolved NO_(3)-.The𝛿15N-NO_(2) and𝛿18O-NO_(2) values suggest that the nitrification process affects the ARB waters,thus controlling the abundances and proportion of the N-species.Our work indicates that additional efforts are needed to improve management strategies to reduce the release of nitrogenated species to the surface waters of the Arno River Basin,since little progress has been made from the early 2000s.展开更多
Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied ...Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied to photocatalytic nitrogen fixation for the first time,and its photocatalytic performance was effectively enhanced through Cu doping.The catalyst was synthesized via a simple reduction method,and its morphology,structure,and physicochemical properties were systematically investigated using various characterization techniques and density functional theory calculations.The results revealed that the incorporation of Cu2+partially replaced Pb2+,inducing lattice distortion in PbBiO_(2)Br,promoting the formation of oxygen vacancies,and modifying its electronic band structure.Specifically,Cu doping led to a slight bandgap narrowing,a reduction in work function,and a significant upward shift in the conduction band position.These changes enhanced light absorption,facilitated charge carrier migration and separation,and improved the reduction ability of photogenerated electrons.Moreover,Cu doping promoted N_(2)adsorption and activation.Consequently,the photocatalytic nitrogen fixation performance of Cu-doped PbBiO_(2)Br was significantly enhanced,achieving an optimal nitrogen fixation rate of 293μmol L^(−1)g^(−1)h^(−1),which is 3.6 times higher than that of pristine PbBiO_(2)Br.Additionally,Cu–PbBiO_(2)Br also showed good activity in the photocatalytic degradation of RhB,with a degradation rate 4.6 times higher than that of PbBiO_(2)Br.This work offers new insights into the application of PbBiO_(2)Br in photocatalytic nitrogen fixation and offers valuable guidance for the development of highly efficient nitrogen fixation materials in the future.展开更多
Liver ischemia-reperfusion injury(LIRI)is a pathological process involving multiple injury factors and cell types,with different stages.Currently,protective drugs targeting a single condition are limited in efficacy,a...Liver ischemia-reperfusion injury(LIRI)is a pathological process involving multiple injury factors and cell types,with different stages.Currently,protective drugs targeting a single condition are limited in efficacy,and interventions on immune cells will also be accompanied by a series of side effects.In the current bottleneck research stage,the multi-target and obvious clinical efficacy of Chinese medicine(CM)is expected to become a breakthrough point in the research and development of new drugs.In this review,we summarize the roles of reactive oxygen species(ROS)and reactive nitrogen species(RNS)in various stages of hepatic ischemia-reperfusion and on various types of cells.Combined with the current research progress in reducing ROS/RNS with CM,new therapies and mechanisms for the treatment of hepatic ischemia-reperfusion are discussed.展开更多
The efficient utilization of photogenerated electrons and the effective activation of reactive molecules are among the major challenges in photocatalytic nitrogen reduction.Defect engineering can enhance the catalyst&...The efficient utilization of photogenerated electrons and the effective activation of reactive molecules are among the major challenges in photocatalytic nitrogen reduction.Defect engineering can enhance the catalyst's ability to adsorb and activate N_(2)and H_(2)O,while the ultrathin structure with maximized active crystal facets can maximize the enrichment of effective photogenerated electrons.This work employs a two-step synergistic method to fabricate ultrathin BiVO_(4)with oxygen vacancies and bismuth vacancies(2D-V_(Bi+O)-BVO,thickness<20 nm)for photocatalytic nitrogen reduction.Scanning electron microscopy,transmission electron microscopy(TEM),and atomic force microscopy characterization confirm the transformation of BiVO_(4)from bulk material(bulk-BVO,~1300 nm)to an ultrathin structure(~15 nm).TEM,X-ray photoelectron spectroscopy,electron paramagnetic resonance characterizations,and density functional theory(DFT)calculations verify the construction of oxygen and bismuth vacancies in the ultrathin BiVO_(4).Compared to bulk-BVO,the photocatalytic nitrogen fixation efficiency of 2D-V_(Bi+O)-BVO is increased by 4.7 times,with the highest activity reaching 158.73μmol·g^(-1)·h^(-1).N_(2)-temperature programmed desorption and DFT calculations demonstrate that the oxygen and bismuth vacancies in BiVO_(4),respectively,promote the adsorption/activation of N_(2)and H_(2)O,which is crucial for the overall nitrogen reduction reaction.Photo-deposition experiments prove that the(040)plane is the active surface for electrons.And the ultrathin structure maximizes the(040)facet of BiVO_(4),which is conducive to the high enrichment of electrons.Meanwhile,more active sites can be exposed for the activation of N_(2)and H_(2)O.In situ infrared spectroscopy confirms that N_(2)can be effectively adsorbed onto 2D-V_(Bi+O)-BVO,and the presence of NH_(2)-NH_(2)active species is consistent with the alternating reaction pathway.This study provides new insights into the development of green and efficient photocatalysts with dual vacancies and ultrathin structures.展开更多
The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge d...The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge distribution of the traditional M-N_(4)active site,the adsorption energy of the key oxygen intermediates in the process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is difficult to reach the optimal value,which seriously limits the catalytic efficiency.The core of solving this problem lies in the accurate modulation of the coordination environment of the M-N_(4)site,which can realize the breakthrough improvement of the catalytic performance by synergistically optimizing the geometric configuration and electronic structure.In this paper,we systematically analyze the ORR/OER reaction mechanism and then comprehensively review the four main strategies to optimize the coordination environment of M-N-C:metal site regulation,coordination number engineering,non-metal atom doping,and carbon support regulation.Through an in-depth analysis of the structure-activity relationship between the coordination configuration and catalytic performance,the core challenges faced by current research are pointed out,and future research directions are envisioned.This work aims to provide theoretical references for the directional construction of highly efficient M-N-C catalysts with optimized coordination environments.展开更多
Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional th...Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical stabilities.The different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic activity.Importantly,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and ORR.These findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts.展开更多
Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalyst...Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalysts.This review synthesizes advances that recast these processes as engineering targets and proposes a conceptual roadmap that bridges synthetic symbioses with the synthetic biology of enzymes and pathways.For BNF,progress spans cross-kingdom strategies—from refactoring nif gene sets and targeting nitrogenase assembly to eukaryotic organelles,to engineering plant-associated diazotrophs,rhizosphere control circuits,and emerging nodule-like microenvironments.For carbon assimilation,new-to-nature CO_(2)-fixation modules and photorespiratory bypasses illustrate how pathway redesign and alternative carboxylases can circumvent key Calvin–Benson–Bassham limitations,and expanding photosynthetic light capture offers additional leverage.Across these domains,we extract common design principles:(i)nitrogenase output is increasingly governed by carbon/energy supply and electron delivery as much as by oxygen protection;(ii)robust function requires compartment-aware enzyme–chassis coordination,substrate channeling,and dynamic regulation using sensors and control circuits;and(iii)scalable implementation may benefit from distributing metabolic labor across engineered consortia rather than forcing all functions into a single host.We discuss enabling technologies—including AI-guided protein design and directed evolution,cell-free prototyping,chassis toolkits,and materials/bioelectrochemical interfaces—that can accelerate design–build–test–learn cycles and reduce barriers to deployment.Together,these insights define a path toward integrated nitrogen and carbon fixation systems for low-emission agriculture and biomanufacturing.展开更多
It is necessary to adopt a specific strategy to construct an efficient and low-cost transition metal-based composite to replace the precious metal-based electrocatalyst for OER catalytic processes.In this work,a beade...It is necessary to adopt a specific strategy to construct an efficient and low-cost transition metal-based composite to replace the precious metal-based electrocatalyst for OER catalytic processes.In this work,a beaded stream-like N and P-codoped carbon-coated Fe_(3)O_(4)nanocomposite(N,P-Fe_(3)O_(4)@C)is derived from MIL-88A by two-step annealing.The unique 3D nanostructure and amorphous N-doped carbon layer enlarge the number of active sites,and P doping changes the pathway from AEM to LOM.The synergistic effect of these factors results in N,P-Fe_(3)O_(4)@C presenting excellent OER catalytic activity with an overpotential of 201 mV(η10),a Tafel slope of 57.1 mV/dec and stable operation for 100 h(the current density is 10 mA/cm^(2)).Density functional theory calculations and electrochemical tests reveal that the P doping enhances the overlap of Fe 3d orbital bands and O 2p orbitals,and thus significantly increases the metaloxygen covalency,triggering the pathway transition from AEM to LOM.This work provides a new way to construct more efficient transition metal-based composite carbon materials.展开更多
Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associate...Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associated with important reduction reactions,such as oxygen reduction reaction(ORR),which leads to the production of hydrogen peroxide(H_(2)O_(2)).These transitions are instrumental in the emergence and evolution of life.In this study,transition metals were loaded onto nitrogen-doped carbon(NDC)prepared under the primitive Earth's atmospheric conditions.These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination.The chemical pathways initiated by the pristine and metal-loaded NDC were investigated.This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.展开更多
As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)poss...As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.展开更多
Transition metal-nitrogen-carbon(M-N-C)with 3d transition metals as noble metal-free catalyzing oxygen reduction reaction(ORR)electrocatalysts still face critical challenges in activity and durability due to the Fento...Transition metal-nitrogen-carbon(M-N-C)with 3d transition metals as noble metal-free catalyzing oxygen reduction reaction(ORR)electrocatalysts still face critical challenges in activity and durability due to the Fenton effect associated with these metals in practical application.To tackle the issue,herein,we report Fenton-inactive rare earth metal La-N-C with dual active sites for efficient ORR,which was synthesized by pyrolyzing a mixed complexing compound of 1,10-phenanthroline as ligand with LaCl_(3)and MgCl_(2)as an activation agent.The as-synthesized La-N-C features an abundant microporous structure with atomically dispersed LaN_(4)O moieties as new active sites,exhibiting outstanding ORR performance.Its half-wave potentials are 0.92 and 0.76 V in 0.1 M KOH and 0.5 M H_(2)SO_(4)respectively,and only a 10 mV half-wave potential loss after 50 K cycles in 0.1 M KOH,achieving the highest level of current non-3d M-N-C ORR electrocatalysts.Meanwhile,the ORR activity is further validated by efficient performance with a power density output of 211 and 480 mW cm^(-2)on a single Zn-air battery and proton exchange membrane fuel cell respectively.Furthermore,theoretical calculations confirm that the unique LaN_(4)O moiety adjacent to the microspore vacancy with graphitic N dopant not only presents a negative shift of the La 5d orbitals,significantly lowering the adsorption energy of*OOH in ORR,but also induces the carbon atom near the graphitic N as one more active site for ORR.This work highlights the potential application of La-N-C as an efficient ORR catalyst in green energy conversion devices.展开更多
A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and...A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.展开更多
Herein,vacancy engineering is utilized reasonably to explore molybdenum tungsten oxide nanowires(W_(4)MoO_(3)NWs)rich in O-vacancies as an advanced electrochemical nitrogen reduction reaction(eNRR)electrocatalyst,real...Herein,vacancy engineering is utilized reasonably to explore molybdenum tungsten oxide nanowires(W_(4)MoO_(3)NWs)rich in O-vacancies as an advanced electrochemical nitrogen reduction reaction(eNRR)electrocatalyst,realizing further enhancement of NRR performance.In 0.1 mol/L Na_(2)SO_(4),W_(4)MoO_(3)NWs rich in O vacancies(CTAB-D-W_(4)MoO_(3))achieve a large NH3yield of 60.77μg h^(-1)mg^(-1)cat.at-0.70 V vs.RHE and a high faradaic efficiency of 56.42%at-0.60 V,much superior to the W_(4)MoO_(3)NWs deficient in oxygen vacancies(20.26μg h^(-1)mg^(-1)cat.and 17.1%at-0.70 V vs.RHE).Meanwhile,W_(4)MoO_(3)NWs rich in O-vacancies also show high electrochemical stability.Density functional theory(DFT)calculations present that O vacancies in CTAB-D-W_(4)MoO_(3)reduce the energy barrier formed by the intermediate of^(*)N-NH,facilitate the activation and further hydrogenation of^(*)N-N,promote the NRR process,and improve NRR activity.展开更多
Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping...Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping and defect engineering can efficiently increase the oxygen reduction reaction(ORR)ability of inactive carbons through charge redistribution.Herein,we report that an enhanced built-in electric field caused by the combined effect of N-doping and carbon defects in the twodimensional(2D)mesoporous N-doped carbon nano flakes(NCNF)is a promising technique for improving ORR performance.As a result,the NCNF exhibits more promising ORR activity than Pt/C and similar performance with reported robust catalysts.Comprehensive experimental and theoretical investigations suggest that topologically defected carbon adjacent to the graphitic valley nitrogen is a real active site,rendering optimal energy for the adsorption of ORR intermediates and lowering the total energy barrier for ORR.Also,NCNF-based Zn-air batteries exhibited an excellent power density and specific capacity of~121.10 mW cm^(-2)and~679.86 mA h g_(Zn)^(-1),respectively.This study not only offers new insights into defected carbons with graphitic valley N for ORR but also proposes novel catalyst design principles and provides a solid grasp of the built-in electric field effect on the ORR performance of defective catalysts.展开更多
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul...The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.展开更多
Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a fo...Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.展开更多
Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and of...Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and offering the highest theoretical energy density(~3.5 k Wh kg^(-1))among discussed candidates.Contributing to the poor cycle life of currently reported Li-O_(2)cells is singlet oxygen(1O_(2))formation,inducing parasitic reactions,degrading key components,and severely deteriorating cell performance.Here,we harness the chirality-induced spin selectivity effect of chiral cobalt oxide nanosheets(Co_(3)O_(4)NSs)as cathode materials to suppress 1O_(2)in Li-O_(2)batteries for the first time.Operando photoluminescence spectroscopy reveals a 3.7-fold and 3.23-fold reduction in 1O_(2)during discharge and charge,respectively,compared to conventional carbon paperbased cells,consistent with differential electrochemical mass spectrometry results,which indicate a near-theoretical charge-to-O_(2)ratio(2.04 e-/O_(2)).Density functional theory calculations demonstrate that chirality induces a peak shift near the Fermi level,enhancing Co 3d-O 2p hybridization,stabilizing reaction intermediates,and lowering activation barriers for Li_(2)O_(2)formation and decomposition.These findings establish a new strategy for improving the stability and energy efficiency of sustainable Li-O_(2)batteries,abridging the current gap to commercialization.展开更多
Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and ma...Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and magnetic field enhanced-electrochemical activity remains to be fully elucidated.Herein,single-domain CoFe_(2)O_(4) catalysts with tunable oxygen vacancies(CFO-V_(O)) were synthesized to probe how V_(O) mediates magnetism and OER activity under magnetic field.The introduction of V_(O) can simultaneously modulate saturation magnetization(M_(s)) and coercivity(H_(c)),where the increased M_(s) dominates the magnetic field-enhanced OER activity.Under a 14,000 G magnetic field,the optimized CFO-V_(O) exhibits up to 16.1 % reduction in overpotential and 365 % enhancement in magnetocurrent(MC).Electrochemical analyses and post-OER characterization reveal that the magnetic field synergistically improves OER kinetics through lattice distortion induction,magnetohydrodynamic effect,and spin charge transfer effect.Importantly,the magnetic field promotes additional Co^(3+) generation to compensate for charge imbalance caused by V_(O) filling,maintaining dynamic equilibrium of V_(O) and effective reactant adsorption-conversion processes.This work unveils the synergistic mechanism of V_(O) and magnetic parameters for enhancing OER performance under the magnetic field,providing new insights into the design of high-efficiency spinregulated OER catalysts.展开更多
基金Project supported by the National Key R&D Program of China (Grant Nos. 2018YFB0406502, 2017YFF0210800, and 2017YFB0403003)the National Natural Science Foundation of China (Grant Nos. 61974059, 61674077, and 61774081)+1 种基金the Natural Science Foundation of Jiangsu Province (Grant No. BK20160065)the Fundamental Research Funds for the Central Universities。
文摘Regulation with nitrogen and oxygen co-doping on growth and properties of boron doped diamond films is studied by using laughing gas as dopant. As the concentration of laughing gas(N2O/C) increases from 0 to 10%, the growth rate of diamond film decreases gradually, and the nitrogen-vacancy(NV) center luminescence intensity increases first and then weakens. The results show that oxygen in laughing gas has a strong inhibitory effect on formation of NV centers, and the inhibitory effect would be stronger as the concentration of laughing gas increases. As a result, the film growth rate and nitrogen-related compensation donor decrease, beneficial to increase the acceptor concentration(~3.2×10^(19)cm^(-3)) in the film. Moreover, it is found that the optimal regulation with the quality and electrical properties of boron doped diamond films could be realized by adding appropriate laughing gas, especially the hole mobility(~700cm^(2)/V·s), which is beneficial to the realization of high-quality boron doped diamond films and high-level optoelectronic device applications in the future.
文摘Radiation induced reactive oxygen/nitrogen species (ROS/RNS) are reported to cause lung injuries such as pneumonitis and fibrosis which may be fatal at times. Current study is designed to analyse the radioprotective efficacy of P. hexandrum active principles (G-002M) on lungs of mice exposed to high dose of gamma irradiation (7 Gy). Cellular profiles and inflammatory cell infiltrates of irradiated bronchoalveolar lavage fluid (BALF) have shown correlations with lung pathology. Cell counts were determined in BALF of control, 7 Gy radiation exposed and radiation with G-002M pretreated mice. ROS/Nitric Oxide (NO) production was measured by 2,7?dichlorodihydrofluorescein diacetate (DCF-DA) and diaminofluorescein diacetate (DAF-2DA) through microscopy and flow cytometry respectively. Immunostaining of inducible nitric oxide synthase (iNOS) in BALF cells and lung sections was also observed microscopically. iNOS ex- pression was observed in lungs by western blotting. BALF was also processed to estimate total protein, LDH, and phospholipids content. Catalase, reduced Glutathione (GSH), Glutathione reductase (GR) and lipid peroxidation were estimated in lung tissues. Pre-administration of G-002M significantly decreased radiation mediated neutrophils count in BALF of irradiated mice. ROS generation, iNOS expression, total protein, LDH and phospholipids were found less affected in G-002M pretreated group in comparison to radiation alone group. Radiation exposure to mice was found apparently leading to parenchymal fibrosis, an architectural distortion of the lung tissue with edema, infiltration of inflammatory blood cells with increased immunolabeling of iNOS. G-002M pretreatment significantly countered radiation mediated increased lipid peroxidation and decreased GR, catalase and GSH in mice. Current study demonstrates possible role of P. hexandrum (G-002M) in minimizing lung damage induced by radiation mediated ROS/RNS generation.
文摘The Arno River Basin(Central Italy)is affected by a considerable anthropogenic pressure due to the presence of large cities and widespread industrial and agricultural practices.In this work,26 water samples from the Arno River and its main tributaries were analyzed to assess the water pollution status.The geochemical composition of the Arno River changes from the source(dominated by a Ca-HCO_(3) facies)to the mouth(where a Na-Cl(SO4)chemistry prevails)with an increasing quality deterioration,as suggested by the Chemical Water Quality Index,due to anthropogenic contributions and seawater intrusion before flowing into the Ligurian Sea.The Ombrone and Usciana tributaries introduce anthropogenic pollutants into the Arno River,whilst Elsa tributary supplies significant contents of geogenic sulfate.The concentrations of dissolved nitrate and nitrite(up to 63 and 9 mg/L,respectively)and the respective isotopic values of𝛿15N and𝛿18O were also determined to understand origin and fate of the N-species in the Arno River Basin surface waters.The combined application of𝛿15N-NO_(3) and𝛿18O-NO_(3) and N-source apportionment modelling allowed the identification of soil organic nitrogen and sewage and domestic wastes as primary sources for dissolved NO_(3)-.The𝛿15N-NO_(2) and𝛿18O-NO_(2) values suggest that the nitrification process affects the ARB waters,thus controlling the abundances and proportion of the N-species.Our work indicates that additional efforts are needed to improve management strategies to reduce the release of nitrogenated species to the surface waters of the Arno River Basin,since little progress has been made from the early 2000s.
基金financially supported by the National Natural Science Foundation of China(No.22172144 and 22272151)Key Research and Development Program of Zhejiang Province(2023C03148).
文摘Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied to photocatalytic nitrogen fixation for the first time,and its photocatalytic performance was effectively enhanced through Cu doping.The catalyst was synthesized via a simple reduction method,and its morphology,structure,and physicochemical properties were systematically investigated using various characterization techniques and density functional theory calculations.The results revealed that the incorporation of Cu2+partially replaced Pb2+,inducing lattice distortion in PbBiO_(2)Br,promoting the formation of oxygen vacancies,and modifying its electronic band structure.Specifically,Cu doping led to a slight bandgap narrowing,a reduction in work function,and a significant upward shift in the conduction band position.These changes enhanced light absorption,facilitated charge carrier migration and separation,and improved the reduction ability of photogenerated electrons.Moreover,Cu doping promoted N_(2)adsorption and activation.Consequently,the photocatalytic nitrogen fixation performance of Cu-doped PbBiO_(2)Br was significantly enhanced,achieving an optimal nitrogen fixation rate of 293μmol L^(−1)g^(−1)h^(−1),which is 3.6 times higher than that of pristine PbBiO_(2)Br.Additionally,Cu–PbBiO_(2)Br also showed good activity in the photocatalytic degradation of RhB,with a degradation rate 4.6 times higher than that of PbBiO_(2)Br.This work offers new insights into the application of PbBiO_(2)Br in photocatalytic nitrogen fixation and offers valuable guidance for the development of highly efficient nitrogen fixation materials in the future.
基金Supported by the National Natural Science Foundation of China(No.82074131 and 82374270)Guangzhou Basic and Applied Basic Research Foundation(No.SL2023A03J01172)+1 种基金the Outstanding Youth Development Scheme Project of Southern Medical University(No.G621299870)Young Elite Scientists Sponsorship Program by CACM(No.2021-QNRC2-B28)。
文摘Liver ischemia-reperfusion injury(LIRI)is a pathological process involving multiple injury factors and cell types,with different stages.Currently,protective drugs targeting a single condition are limited in efficacy,and interventions on immune cells will also be accompanied by a series of side effects.In the current bottleneck research stage,the multi-target and obvious clinical efficacy of Chinese medicine(CM)is expected to become a breakthrough point in the research and development of new drugs.In this review,we summarize the roles of reactive oxygen species(ROS)and reactive nitrogen species(RNS)in various stages of hepatic ischemia-reperfusion and on various types of cells.Combined with the current research progress in reducing ROS/RNS with CM,new therapies and mechanisms for the treatment of hepatic ischemia-reperfusion are discussed.
文摘The efficient utilization of photogenerated electrons and the effective activation of reactive molecules are among the major challenges in photocatalytic nitrogen reduction.Defect engineering can enhance the catalyst's ability to adsorb and activate N_(2)and H_(2)O,while the ultrathin structure with maximized active crystal facets can maximize the enrichment of effective photogenerated electrons.This work employs a two-step synergistic method to fabricate ultrathin BiVO_(4)with oxygen vacancies and bismuth vacancies(2D-V_(Bi+O)-BVO,thickness<20 nm)for photocatalytic nitrogen reduction.Scanning electron microscopy,transmission electron microscopy(TEM),and atomic force microscopy characterization confirm the transformation of BiVO_(4)from bulk material(bulk-BVO,~1300 nm)to an ultrathin structure(~15 nm).TEM,X-ray photoelectron spectroscopy,electron paramagnetic resonance characterizations,and density functional theory(DFT)calculations verify the construction of oxygen and bismuth vacancies in the ultrathin BiVO_(4).Compared to bulk-BVO,the photocatalytic nitrogen fixation efficiency of 2D-V_(Bi+O)-BVO is increased by 4.7 times,with the highest activity reaching 158.73μmol·g^(-1)·h^(-1).N_(2)-temperature programmed desorption and DFT calculations demonstrate that the oxygen and bismuth vacancies in BiVO_(4),respectively,promote the adsorption/activation of N_(2)and H_(2)O,which is crucial for the overall nitrogen reduction reaction.Photo-deposition experiments prove that the(040)plane is the active surface for electrons.And the ultrathin structure maximizes the(040)facet of BiVO_(4),which is conducive to the high enrichment of electrons.Meanwhile,more active sites can be exposed for the activation of N_(2)and H_(2)O.In situ infrared spectroscopy confirms that N_(2)can be effectively adsorbed onto 2D-V_(Bi+O)-BVO,and the presence of NH_(2)-NH_(2)active species is consistent with the alternating reaction pathway.This study provides new insights into the development of green and efficient photocatalysts with dual vacancies and ultrathin structures.
基金supported by the Natural Science Foundation of Hebei Province(no.E2024501010)the National Natural Science Foundation of China(no.52374301)+1 种基金the Shijiazhuang Basic Research Project(no.241790667A)the Performance Subsidy Fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(no.22567627H)。
文摘The development of highly efficient non-precious metal-nitrogen-carbon(M-N-C)electrocatalysts is a key scientific issue for improving the performance of metal-air batteries and fuel cells.Due to the symmetric charge distribution of the traditional M-N_(4)active site,the adsorption energy of the key oxygen intermediates in the process of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is difficult to reach the optimal value,which seriously limits the catalytic efficiency.The core of solving this problem lies in the accurate modulation of the coordination environment of the M-N_(4)site,which can realize the breakthrough improvement of the catalytic performance by synergistically optimizing the geometric configuration and electronic structure.In this paper,we systematically analyze the ORR/OER reaction mechanism and then comprehensively review the four main strategies to optimize the coordination environment of M-N-C:metal site regulation,coordination number engineering,non-metal atom doping,and carbon support regulation.Through an in-depth analysis of the structure-activity relationship between the coordination configuration and catalytic performance,the core challenges faced by current research are pointed out,and future research directions are envisioned.This work aims to provide theoretical references for the directional construction of highly efficient M-N-C catalysts with optimized coordination environments.
基金supported by the National Natural Science Foundation of China(Nos.22102167 and U21A20317)。
文摘Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical stabilities.The different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic activity.Importantly,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and ORR.These findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts.
基金supported by the funds of the Ministry of Science and Technology of China(2019YFA0904700)the National Natural Science Foundation of China(32471477)to Cheng Qi.
文摘Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalysts.This review synthesizes advances that recast these processes as engineering targets and proposes a conceptual roadmap that bridges synthetic symbioses with the synthetic biology of enzymes and pathways.For BNF,progress spans cross-kingdom strategies—from refactoring nif gene sets and targeting nitrogenase assembly to eukaryotic organelles,to engineering plant-associated diazotrophs,rhizosphere control circuits,and emerging nodule-like microenvironments.For carbon assimilation,new-to-nature CO_(2)-fixation modules and photorespiratory bypasses illustrate how pathway redesign and alternative carboxylases can circumvent key Calvin–Benson–Bassham limitations,and expanding photosynthetic light capture offers additional leverage.Across these domains,we extract common design principles:(i)nitrogenase output is increasingly governed by carbon/energy supply and electron delivery as much as by oxygen protection;(ii)robust function requires compartment-aware enzyme–chassis coordination,substrate channeling,and dynamic regulation using sensors and control circuits;and(iii)scalable implementation may benefit from distributing metabolic labor across engineered consortia rather than forcing all functions into a single host.We discuss enabling technologies—including AI-guided protein design and directed evolution,cell-free prototyping,chassis toolkits,and materials/bioelectrochemical interfaces—that can accelerate design–build–test–learn cycles and reduce barriers to deployment.Together,these insights define a path toward integrated nitrogen and carbon fixation systems for low-emission agriculture and biomanufacturing.
基金the National Nature Science Foundation of China(No.22304021)National Key Research and Development Project(No.2022YFA1505300)Sichuan Department of Science and Technology Program of China(No.2022YFG0312)for financial support。
文摘It is necessary to adopt a specific strategy to construct an efficient and low-cost transition metal-based composite to replace the precious metal-based electrocatalyst for OER catalytic processes.In this work,a beaded stream-like N and P-codoped carbon-coated Fe_(3)O_(4)nanocomposite(N,P-Fe_(3)O_(4)@C)is derived from MIL-88A by two-step annealing.The unique 3D nanostructure and amorphous N-doped carbon layer enlarge the number of active sites,and P doping changes the pathway from AEM to LOM.The synergistic effect of these factors results in N,P-Fe_(3)O_(4)@C presenting excellent OER catalytic activity with an overpotential of 201 mV(η10),a Tafel slope of 57.1 mV/dec and stable operation for 100 h(the current density is 10 mA/cm^(2)).Density functional theory calculations and electrochemical tests reveal that the P doping enhances the overlap of Fe 3d orbital bands and O 2p orbitals,and thus significantly increases the metaloxygen covalency,triggering the pathway transition from AEM to LOM.This work provides a new way to construct more efficient transition metal-based composite carbon materials.
基金supported by the National Key Technologies R&D Program of China(Nos.2022YFE0114800 and 2021YFA1502100)National Natural Science Foundation of China(Nos.22075047,22032002,U1905214,21961142019)the 111 Project(Nos.D16008)。
文摘Solar-induced water oxidation reaction(WOR)for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages.WOR is also associated with important reduction reactions,such as oxygen reduction reaction(ORR),which leads to the production of hydrogen peroxide(H_(2)O_(2)).These transitions are instrumental in the emergence and evolution of life.In this study,transition metals were loaded onto nitrogen-doped carbon(NDC)prepared under the primitive Earth's atmospheric conditions.These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination.The chemical pathways initiated by the pristine and metal-loaded NDC were investigated.This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22178148 and 22278193)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.
基金financially supported by the National Natural Science Foundation of China(22075055)the Guangxi Science and Technology Project(AB16380030)。
文摘Transition metal-nitrogen-carbon(M-N-C)with 3d transition metals as noble metal-free catalyzing oxygen reduction reaction(ORR)electrocatalysts still face critical challenges in activity and durability due to the Fenton effect associated with these metals in practical application.To tackle the issue,herein,we report Fenton-inactive rare earth metal La-N-C with dual active sites for efficient ORR,which was synthesized by pyrolyzing a mixed complexing compound of 1,10-phenanthroline as ligand with LaCl_(3)and MgCl_(2)as an activation agent.The as-synthesized La-N-C features an abundant microporous structure with atomically dispersed LaN_(4)O moieties as new active sites,exhibiting outstanding ORR performance.Its half-wave potentials are 0.92 and 0.76 V in 0.1 M KOH and 0.5 M H_(2)SO_(4)respectively,and only a 10 mV half-wave potential loss after 50 K cycles in 0.1 M KOH,achieving the highest level of current non-3d M-N-C ORR electrocatalysts.Meanwhile,the ORR activity is further validated by efficient performance with a power density output of 211 and 480 mW cm^(-2)on a single Zn-air battery and proton exchange membrane fuel cell respectively.Furthermore,theoretical calculations confirm that the unique LaN_(4)O moiety adjacent to the microspore vacancy with graphitic N dopant not only presents a negative shift of the La 5d orbitals,significantly lowering the adsorption energy of*OOH in ORR,but also induces the carbon atom near the graphitic N as one more active site for ORR.This work highlights the potential application of La-N-C as an efficient ORR catalyst in green energy conversion devices.
文摘A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure.
基金supported by the National Natural Science Foundation of China(No.51872173)Natural Science Foundation of Shandong Province(No.ZR2022JQ21)。
文摘Herein,vacancy engineering is utilized reasonably to explore molybdenum tungsten oxide nanowires(W_(4)MoO_(3)NWs)rich in O-vacancies as an advanced electrochemical nitrogen reduction reaction(eNRR)electrocatalyst,realizing further enhancement of NRR performance.In 0.1 mol/L Na_(2)SO_(4),W_(4)MoO_(3)NWs rich in O vacancies(CTAB-D-W_(4)MoO_(3))achieve a large NH3yield of 60.77μg h^(-1)mg^(-1)cat.at-0.70 V vs.RHE and a high faradaic efficiency of 56.42%at-0.60 V,much superior to the W_(4)MoO_(3)NWs deficient in oxygen vacancies(20.26μg h^(-1)mg^(-1)cat.and 17.1%at-0.70 V vs.RHE).Meanwhile,W_(4)MoO_(3)NWs rich in O-vacancies also show high electrochemical stability.Density functional theory(DFT)calculations present that O vacancies in CTAB-D-W_(4)MoO_(3)reduce the energy barrier formed by the intermediate of^(*)N-NH,facilitate the activation and further hydrogenation of^(*)N-N,promote the NRR process,and improve NRR activity.
基金supported by the National Natural Science Foundation of China(22262010,22062005,22165005,U20A20128)Guangxi Science and Technology Fund for Distinguished HighTalent Introduction Program(AC22035091)Guangxi Science Fund for Distinguished Young Scholars(2019GXNSFFA245016)。
文摘Rational design of defected carbons adjacent to nitrogen(N)dopants is a fascinating but challenging approach for enhancing the catalytic performance of N-doped carbon.Meanwhile,the combined effect of heteroatom doping and defect engineering can efficiently increase the oxygen reduction reaction(ORR)ability of inactive carbons through charge redistribution.Herein,we report that an enhanced built-in electric field caused by the combined effect of N-doping and carbon defects in the twodimensional(2D)mesoporous N-doped carbon nano flakes(NCNF)is a promising technique for improving ORR performance.As a result,the NCNF exhibits more promising ORR activity than Pt/C and similar performance with reported robust catalysts.Comprehensive experimental and theoretical investigations suggest that topologically defected carbon adjacent to the graphitic valley nitrogen is a real active site,rendering optimal energy for the adsorption of ORR intermediates and lowering the total energy barrier for ORR.Also,NCNF-based Zn-air batteries exhibited an excellent power density and specific capacity of~121.10 mW cm^(-2)and~679.86 mA h g_(Zn)^(-1),respectively.This study not only offers new insights into defected carbons with graphitic valley N for ORR but also proposes novel catalyst design principles and provides a solid grasp of the built-in electric field effect on the ORR performance of defective catalysts.
文摘The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.
基金support from the National Natural Science Foundation of China(Nos.12305373 and 52276220)the Guangzhou Basic Research Program(No.SL2024A04J00234).
文摘Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.
基金supported by Basic Science Research Program(Priority Research Institute)through the NRF of Korea funded by the Ministry of Education(2021R1A6A1A10039823)by the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Ministry of Education(2020R1A6C101B194)。
文摘Lithium-oxygen(Li-O2)batteries are perceived as a promising breakthrough in sustainable electrochemical energy storage,utilizing ambient air as an energy source,eliminating the need for costly cathode materials,and offering the highest theoretical energy density(~3.5 k Wh kg^(-1))among discussed candidates.Contributing to the poor cycle life of currently reported Li-O_(2)cells is singlet oxygen(1O_(2))formation,inducing parasitic reactions,degrading key components,and severely deteriorating cell performance.Here,we harness the chirality-induced spin selectivity effect of chiral cobalt oxide nanosheets(Co_(3)O_(4)NSs)as cathode materials to suppress 1O_(2)in Li-O_(2)batteries for the first time.Operando photoluminescence spectroscopy reveals a 3.7-fold and 3.23-fold reduction in 1O_(2)during discharge and charge,respectively,compared to conventional carbon paperbased cells,consistent with differential electrochemical mass spectrometry results,which indicate a near-theoretical charge-to-O_(2)ratio(2.04 e-/O_(2)).Density functional theory calculations demonstrate that chirality induces a peak shift near the Fermi level,enhancing Co 3d-O 2p hybridization,stabilizing reaction intermediates,and lowering activation barriers for Li_(2)O_(2)formation and decomposition.These findings establish a new strategy for improving the stability and energy efficiency of sustainable Li-O_(2)batteries,abridging the current gap to commercialization.
基金supported by the “Climbing Plan” of Harbin Normal University (No.XKB202301)National Natural Science Foundation of China (Nos.21871065 and 22071038)。
文摘Magnetic field-driven spin polarization modulation has emerged as an effective way to boost the electrocatalytic oxygen evolution reaction(OER).However,the correlation among catalyst structure,magnetic property,and magnetic field enhanced-electrochemical activity remains to be fully elucidated.Herein,single-domain CoFe_(2)O_(4) catalysts with tunable oxygen vacancies(CFO-V_(O)) were synthesized to probe how V_(O) mediates magnetism and OER activity under magnetic field.The introduction of V_(O) can simultaneously modulate saturation magnetization(M_(s)) and coercivity(H_(c)),where the increased M_(s) dominates the magnetic field-enhanced OER activity.Under a 14,000 G magnetic field,the optimized CFO-V_(O) exhibits up to 16.1 % reduction in overpotential and 365 % enhancement in magnetocurrent(MC).Electrochemical analyses and post-OER characterization reveal that the magnetic field synergistically improves OER kinetics through lattice distortion induction,magnetohydrodynamic effect,and spin charge transfer effect.Importantly,the magnetic field promotes additional Co^(3+) generation to compensate for charge imbalance caused by V_(O) filling,maintaining dynamic equilibrium of V_(O) and effective reactant adsorption-conversion processes.This work unveils the synergistic mechanism of V_(O) and magnetic parameters for enhancing OER performance under the magnetic field,providing new insights into the design of high-efficiency spinregulated OER catalysts.
