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Phase transformation behavior of galena during oxygen pressure leaching in H_(2)SO_(4)-Fe_(2)(SO_(4))_(3) system
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作者 SUN Pu BAO Chong-jun +4 位作者 WANG Ji-bo LI Xing-bin WEI Chang DENG Zhi-gan LI Min-ting 《Journal of Central South University》 2025年第8期2894-2911,共18页
The phase transformation of galena in H_(2)SO_(4)-Fe_(2)(SO_(4))_(3) system under oxygen pressure was investigated.Results indicated that the critical conditions for the phase transformation of galena into lead jarosi... The phase transformation of galena in H_(2)SO_(4)-Fe_(2)(SO_(4))_(3) system under oxygen pressure was investigated.Results indicated that the critical conditions for the phase transformation of galena into lead jarosite(Pb-J)were 130℃,30 g/L H_(2)SO_(4),15 g/L Fe^(3+),and an oxygen partial pressure of 0.4 MPa.Furthermore,increased Fe^(3+)concentration and oxygen partial pressure did not enhance jarosite formation.Conversely,lowering the temperature and increasing the H_(2)SO_(4) concentration facilitated PbSO_(4) formation and inhibited its further conversion to Pb-J.Additionally,the effects of potassium sulfate,sodium sulfate,and high concentrations of zinc sulfate on the phase transformation of galena were examined through leaching tests,XRD,SEM-EDS,and FT-IR analyses.All three sulfates inhibited the conversion of galena to Pb-J.Among these,potassium sulfate prevented Pb-J formation and converted it more thoroughly into potassium jarosite.However,high concentrations of zinc sulfate facilitated the crystallization of both PbSO_(4) and Pb-J,which altered the morphology of the product.Zinc ions coprecipitated with Pb-J,thereby integrating into the product. 展开更多
关键词 GALENA phase transformation lead sulfate lead jarosite oxygen pressure leaching
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Assessing the impact of climate change on dissolved oxygen using a flow field ecosystem model that takes into account the anaerobic and aerobic environment of bottom sediments
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作者 Jinichi Koue 《Acta Geochimica》 2025年第1期11-22,共12页
This study examines the potential impacts o climate change on Lake Biwa,Japan’s largest freshwate lake,with a focus on temperature,wind speed,and pre cipitation variations.Leveraging data from the IPCC Sixth Assessme... This study examines the potential impacts o climate change on Lake Biwa,Japan’s largest freshwate lake,with a focus on temperature,wind speed,and pre cipitation variations.Leveraging data from the IPCC Sixth Assessment Report,including CCP scenarios,projecting a significant temperature rise of 3.3–5.7℃in the case o very high GHG emission power,the research investigates how these shifts may influence dissolved oxygen levels in Lake Biwa.Through a one-dimensional model incorporat ing sediment redox reactions,various scenarios where ai temperature and wind speed are changed are simulated.I is revealed that a 5℃increase in air temperature leads to decreasing 1-2 mg/L of dissolved oxygen concentrations from the surface layer to the bottom layer,while a decrease in air temperature tends to elevate 1–3 mg/L of oxygen lev els.Moreover,doubling wind speed enhances surface laye oxygen but diminishes it in deeper layers due to increased mixing.Seasonal variations in wind effects are noted with significant surface layer oxygen increases from 0.4to 0.8 mg/L during summer to autumn,increases from 0.4 to 0.8 mg/L in autumn to winter due to intensified vertica mixing.This phenomenon impacts the lake’s oxygen cycle year-round.In contrast,precipitation changes show limited impact on oxygen levels,suggesting minor influence com pared to other meteorological factors.The study suggests the necessity of comprehensive three-dimensional models that account for lake-specific and geographical factors fo accurate predictions of future water conditions.A holistic approach integrating nutrient levels,water temperature,and river inflow is deemed essential for sustainable management of Lake Biwa’s water resources,particularly in addressing precipitation variations. 展开更多
关键词 Climate change Dissolved oxygen Sediment redox reaction Stratifi cation Water quality
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CoMoNiO-S/nickel foam heterostructure composite for efficient oxygen evolution catalysis performance
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作者 YANG Hong SHAO Shengjuan +2 位作者 LI Baoyi LU Yifan LI Na 《无机化学学报》 北大核心 2026年第1期203-215,共13页
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
关键词 oxygen evolution reaction VULCANIZATION composite electrocatalyst MoNi-based catalyst
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Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
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作者 ZHENG Haifeng GUO Xingzhe +5 位作者 WEI Yunwei WANG Xinfang QI Huimin YAN Yuting ZHANG Jie LI Bingwen 《无机化学学报》 北大核心 2026年第1期193-202,共10页
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
关键词 PYRENE metal-organic frameworks composite catalyst oxygen evolution reaction density functional theory
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Chemical-looping methane hydrogen production performance of Cu,La,Ce modified Fe_(2)O_(3)/Al_(2)O_(3)oxygen carrier
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作者 YANG Liangnuo LI Yilong +6 位作者 ZHOU Zheng DENG Chunhuan MA Hao DING Zisheng LI Guoliang LI Ming GU Zhenhua 《燃料化学学报(中英文)》 北大核心 2026年第4期82-95,共14页
Chemical looping methane steam reforming(CL-MSR)has garnered significant attention owing to its ability to sequentially produce syngas with high selectivity and high-purity hydrogen through redox cycling.To overcome t... Chemical looping methane steam reforming(CL-MSR)has garnered significant attention owing to its ability to sequentially produce syngas with high selectivity and high-purity hydrogen through redox cycling.To overcome the limitations of single ironbased oxygen carriers,including poor cycling stability,low reactivity and susceptibility to sintering,this study employed a dipcoating method to modify Fe_(2)O_(3)/Al_(2)O_(3)oxygen carriers by incorporating three distinct metal additives:Cu,La and Ce.The composite oxygen carriers were systematically characterized and evaluated under redox conditions to investigate the structure-activity relationships between the physicochemical properties,reactivity,and hydrogen production performance.Results revealed that the spinel-phase CuFe_(2)O_(4)exhibited higher reactivity than the perovskite-phase LaFeO_(3)and CeO_(2),promoting the deeper reduction of Fe_(2)O_(3).Fe58Cu2Al exhibited an oxygen storage capacity as high as 6.5 mmol/g.During the CH4 reaction stage,Fe58Cu2Al achieved the highest oxygen loss of 12.1 g/100 g oxygen carrier,accompanied by a syngas yield of 5.15 mmol/g-1.33 times and 1.59 times greater than that of Fe60Al.In the hydrogen production stage,the 2%Cu-modified oxygen carrier demonstrated optimal performance,yielding 5.13 mmol/g of hydrogen,which was 1.51 times that of the pristine sample.Even after ten cycles,the H_(2)yield remained at 3.61 mmol/g,surpassing the single-cycle output of the pristine sample and the H2 purity consistently exceeded 98%. 展开更多
关键词 chemical looping iron-based oxygen carrier metal promoter hydrogen purity
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Abiotic aerobic oxidation pathways of stibnite revealed by oxygen and sulfur isotope systematics of sulfate
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作者 Ningjie He Shu Li +3 位作者 Xiaoqian Li Yaning Tang Jiaxue Yang Jianwei Zhou 《Journal of Environmental Sciences》 2025年第1期83-92,共10页
The environmental threat posed by stibnite is an important geoenvironmental issue of current concern.To better understand stibnite oxidation pathways,aerobic abiotic batch experiments were conducted in aqueous solutio... The environmental threat posed by stibnite is an important geoenvironmental issue of current concern.To better understand stibnite oxidation pathways,aerobic abiotic batch experiments were conducted in aqueous solution with varyingδ^(18)O_(H_(2)O) value at initial neutral pH for different lengths of time(15-300 days).The sulfate oxygen and sulfur isotope compositions as well as concentrations of sulfur and antimony species were determined.The sulfur isotope fractionation factor(△^(34)S_(SO4-stibnite))values decreased from 0.8‰to-2.1‰during the first 90 days,and increased to 2.6‰at the 180 days,indicating the dominated intermediate sulfur species such as S_(2)O_(3)^(2-),S0,and H_(2)S(g)involved in Sb2S3 oxidation processes.The incorporation of O into sulfate derived from O_(2)(~100%)indicated that the dissociated O_(2)was only directly adsorbed on the stibnite-S sites in the initial stage(0-90 days).The proportion of O incorporation into sulfate from water(27%-52%)increased in the late stage(90-300 days),which suggested the oxidation mechanism changed to hydroxyl attack on stibnite-S sites promoted by nearby adsorbed O_(2)on stibnite-Sb sites.The exchange of oxygen between sulfite and water may also contributed to the increase of water derived O into SO42-.The new insight of stibnite oxidation pathway contributes to the understanding of sulfide oxidation mechanism and helps to interpret field data. 展开更多
关键词 Sulfide oxidation δ^(34)S_(SO4) δ^(18)O_(SO4) oxygen source of sulfate
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Hydrothermal carbon with abundant oxygen-containing functional groups for photocatalytic H_(2)O_(2)generation in water and seawater
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作者 CHANG Yuhong HAN Xue +5 位作者 ZHANG Yanxia LI Guofang HU Tianjun CHEN Wenwen PEI Linjuan JIA Jianfeng 《燃料化学学报(中英文)》 北大核心 2026年第4期160-170,共11页
Photosynthesis of H_(2)O_(2)via sustainable biomass-derived carbon catalysts facilitate the conversion of renewable resources into valuable chemicals.However,the regulatory function of surface functional groups over r... Photosynthesis of H_(2)O_(2)via sustainable biomass-derived carbon catalysts facilitate the conversion of renewable resources into valuable chemicals.However,the regulatory function of surface functional groups over reaction kinetics has not been sufficiently investigated.Herein,hydrothermal carbon spheres(CS)rich in oxygencontaining functional groups demonstrated a remarkably high H_(2)O_(2)production rate(653μmol/(g·h))in both pure water and actual seawater,even in the absence of any sacrificial agent.Meanwhile,the catalyst demonstrates outstanding activity(92%conversion and>99%selectivity)in the visible-light-driven photocatalytic oxidation of benzylamine to imines.Comprehensive analysis reveals that CS was rich in surface oxygen-containing functional groups,a feature strongly associated with its high photocatalytic efficiency.The observed positive Zeta potential of CS in seawater likely diminished the electrostatic repulsion against the positively charged intermediates,thereby facilitating their accumulation at the liquid-solid interface.This work proposes a strategic framework for developing metal-free photocatalysts from biomass,offering a sustainable pathway for photocatalytic applications. 展开更多
关键词 hydrothermal carbon oxygen functional groups photocatalytic H_(2)O_(2)production benzylamine coupling
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Synergistic enhancement of visible-light photocatalytic methyl orange degradation via oxygen vacancy TiO_(2)/Sn_(3)O_(4) composites
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作者 Cailing Jia Zhanting Zhang +4 位作者 Fuwei Yan Fuyue Liu Yanni Wu Fen Wang Haijiao Xie 《日用化学工业(中英文)》 北大核心 2026年第2期191-200,共10页
The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsor... The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications. 展开更多
关键词 TiO_(2)/Sn_(3)O_(4)composite visible-light photocatalysis methyl orange degradation oxygen vacancies hydroxyl radicals
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Synergistic Oxygen Vacancy and Ru-N Coordination in RuO_(2)@NCC for Enhanced Acidic Oxygen Evolution Reaction
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作者 Mi Luo Linyao Huang +2 位作者 Chen Shen Tianhua Yang Chenguang Wang 《Carbon Energy》 2026年第1期115-125,共11页
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
关键词 OVSM-LOM oxygen evolution reaction oxygen vacancy Ru-N XAFS
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Chirality-Induced Suppression of Singlet Oxygen in Lithium-Oxygen Batteries with Extended Cycle Life
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作者 Kyunghee Chae Youngbi Kim +11 位作者 Yookyeong Oh Hosik Hahn Jaehyun Son Youngsin Kim Hyuk‑Joon Kim Hyun Jeong Lee Dohyub Jang Jooho Moon Kisuk Kang Jeong Woo Han Filipe Marques Mota Dong Ha Kim 《Nano-Micro Letters》 2026年第2期124-137,共14页
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
关键词 Singlet oxygen suppression Chirality-induced spin selectivity effect Lithium–oxygen batteries oxygen evolution reaction Battery stability
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Spin-State Engineering via Cr^(3+) Incorporation in Co_(3)O_(4) Spinel for Efficient Bifunctional Oxygen Electrocatalysis
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作者 Guangjian Xing Mingwang Lu +6 位作者 Guanhua Zhang Qitong Sheng Xiaojing Yang Xiaofei Yu Xinghua Zhang Zunming Lu Lanlan Li 《Carbon Energy》 2026年第3期151-161,共11页
The primary challenge in rechargeable Zn-air batteries lies in developing a catalyst capable of simultaneously improving performance for oxygen reduction reaction(ORR)during discharge and oxygen evolution reaction(OER... The primary challenge in rechargeable Zn-air batteries lies in developing a catalyst capable of simultaneously improving performance for oxygen reduction reaction(ORR)during discharge and oxygen evolution reaction(OER)during charge.Engineering spin configuration is essential for enhancing the intrinsic bifunctional activity and stability of spinel Co_(3)O_(4).Herein,Cr^(3+)is doped into Co_(3)O_(4),inducing directional distortion of CoO_6 octahedron to modify crystal field splitting energy,pushing Co_(Oh)toward intermediate-spin(IS)configuration(t_(2g)^(5)e_(g^(1)))with optimized eg occupancy of 1.04.As a result,9%Cr-Co_(3)O_(4)demonstrates an excellent bifunctional activity and remarkable rechargeable Zn-air battery performance that even outperforms Pt/C+RuO_(2).Density functional theory(DFT)studies reveal that IS Co_(Oh)not only regulates the adsorption energy of ORR/OER species but also transform the O_(2)adsorption configuration from end-on to Griffith configuration,thus modifies the mechanisms of both ORR and OER process and optimize bifunctional activity and selectivity.This work provides mechanistic insight into the spin origin of ORR/OER catalysis and highlights a promising strategy for developing robust bifunctional electrocatalysts. 展开更多
关键词 oxygen electrocatalysis oxygen evolution reaction oxygen reduction reaction spin state spinel Co_(3)O_(4)
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Improvement of high-temperature oxygen reduction catalytic performance of medium-entropy perovskite by modulating the distribution of localized electrons
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作者 Chao Huang Zixuan Tang +4 位作者 Yingnan Dou Liping Sun Qiang Li Lihua Huo Hui Zhao 《Journal of Energy Chemistry》 2026年第2期881-892,I0019,共13页
High-entropy oxides(HEOs)derive their exceptional properties from the atomic-level homogenization of multiple constituent elements within the crystal lattice,which induces a sophisticated local environment that fundam... High-entropy oxides(HEOs)derive their exceptional properties from the atomic-level homogenization of multiple constituent elements within the crystal lattice,which induces a sophisticated local environment that fundamentally reconfigures electron density distributions and coordination environment at active sites.However,the mechanisms by which multi-component systems in HEOs precisely regulate high-activity catalytic sites remain poorly understood.This work addresses this gap by designing medium-entropy perovskite oxides through the strategic incorporation of transition metals with distinct electronegativities and ionic radii,aiming to unravel how local environmental modifications impact the energy band location,coordination states,and adsorption behavior of the Co site.A family of A_(2)BO_(4)-type medium-entropy oxides PrSr(Fe_(0.2)Co_(0.2)Ni_(0.2)Cu_(0.2)M_(0.2))O_(4)(M=Sc,Cr,Mn)was successfully synthesized.Divergent atomic properties among Sc,Cr,and Mn(electronegativity,ionic size,and metal-oxygen bond strength)triggered pronounced electron redistribution,effectively tuning the d-band center of Co.Remarkably,Cr substitution significantly enhanced O_(2) adsorption at Co-active sites,as indicated by an elongated O-O bond length(1.234Å→1.279Å).Concurrently,Cr doping destabilized the M'-O-Cr bonds(M'=Fe,Co,Ni,Cu)and lowered the thermodynamic barrier for oxygen vacancy formation.Electrochemical tests revealed that PrSr(Fe_(0.2)Co_(0.2)Ni_(0.2)Cu_(0.2)Cr_(0.2))O_(4)(PSMO-Cr)exhibited the highest electrical conductivity and fastest oxygen surface exchange kinetics.At 700℃,the area-specific resistance(ASR)of the PSMO-Cr cathode was 0.07Ωcm^(2).Corresponding fuel cells achieved a maximum power density of 0.76 W cm^(-2).In electrolysis mode,the maximum current density reached 0.56 A cm^(-2) under 1.3 V at 700℃using PSMO-Cr as the anode.These results demonstrate that PSMO-Cr is a promising bifunctional catalyst for energy conversion applications. 展开更多
关键词 oxygen reduction reaction oxygen evolution reaction Medium entropy oxides Bi-functional ELECTRONEGATIVITY
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Magnetic field enhanced electrocatalytic oxygen evolution of CoFe_(2)O_(4) with tunable oxygen vacancy concentrations
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作者 Xiangyang Zou Ping Guo +2 位作者 Yuanyuan Zhang Feng Gao Ping Xu 《Chinese Chemical Letters》 2026年第1期671-677,共7页
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
关键词 Spinel oxide oxygen vacancy Magnetic field Magnetic property oxygen evolution reaction
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Manipulating and unveiling contributions of the reactive oxygen species dramatically promote selective photo-oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid in aqueous solution
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作者 Runqing Xiao Qingmao Yang +3 位作者 Yanjie Li Wei Zhang Gang Xiao Chun Shen 《Green Energy & Environment》 2026年第2期488-499,共12页
Achieving high selectivity to 2,5-furandicarboxylic acid(FDCA)in the photocatalytic oxidation of 5-hydroxymethylfurfural(HMF)in aqueous solution advocates the principle of green and sustainable chemistry,but still rem... Achieving high selectivity to 2,5-furandicarboxylic acid(FDCA)in the photocatalytic oxidation of 5-hydroxymethylfurfural(HMF)in aqueous solution advocates the principle of green and sustainable chemistry,but still remains a significant challenge.Herein,manipulating the reactive oxygen species(ROS)has been realized and dramatically promotes the selective photocatalytic oxidation of HMF in aqueous solution.A high FDCAyield of 98.6% has been achieved after 3 h of visible light irradiation over the as-prepared FeO_(x)-Au/TiO_(2) catalyst,being one of the leading photocatalytic performances.Furthermore,satisfactory FDCA yields of higher than 80%could be realized even in the outdoor environment under natural sunlight irradiation,regardless of sunny or cloudy weather.A combination study including physical characterization,kinetic analysis,radical trapping experiments and density functional theory calculations unveils the rate-determining step(oxidation of hydroxyl group)and respective contributions of the generated ROS(1O_(2) and·O_(2)-)in each step of the entire reaction network.The present work would push ahead the understanding of HMF photocatalytic oxidation and contribute to the rational design of high-performance photocatalysts. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL 2 5-Furandicarboxylic acid Reactive oxygen species Singlet oxygen Photocatalytic oxidation
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Co-based Bifunctional Electrocatalyst with Sturdy Three-Dimensional Frame Construction for Oxygen Reduction and Oxygen Evolution Reactions
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作者 ZHENG Chenxi CHEN Cheng +1 位作者 LIAO Jun ZHANG Haining 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期346-352,共7页
Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that... Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that the introduction of the silica nanoparticles can stabilize the microstructure of the derived CoN-C materials,which in turn exhibits the promising electrocatalytic activity towards both oxygen reduction and oxygen evolution reactions.The optimized sample exhibits a better oxygen reduction activity than commercial Pt/C catalyst as confirmed by the positive shift of half-wave potential by 20 mV while it has a low overpotential of 273 mV for oxygen evolution reactions with the retained performance over 80%after 25,000 s of continuous operation.It is demonstrated that the introduction of support frame might be an effective way to improve the activity and stability of metal-organic-framework derived electrocatalyst with stabilized microstructure. 展开更多
关键词 ELECTROCATALYST metal organic framework heteroatom doping oxygen reduction reaction oxygen evolution reaction
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Advances of the bifunctional electrocatalyst toward oxygen reduction/evolution reaction
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作者 Yongxia Wang Shuang Li +7 位作者 Mengli Li Xi Luo Yang Zhang Xiangzhi Cui Guicheng Liu Woochul Yang Haitao Huang Jinli Qiao 《Journal of Energy Chemistry》 2026年第3期574-607,共34页
The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeab... The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeable metal-air battery systems.Significant progress has been made in the design of high-performance bifunctional electrocatalysts,the development of novel oxygen electrode architectures,and the in-depth understanding of electrocatalytic mechanisms through combined experimental and computational studies.This work provides a comprehensive review of recent advancements in design strategies for oxygen catalysts,including homogeneous electrodes,asymmetric electrodes,and biomimetic electrodes,are thoroughly discussed and summarized.Then,the advanced catalyst modification strategies for ORR/OER are summarized,focusing on critical factors such as enhancement effect of metal/nonmental and synergistic enhancement effect in multiple catalyst.Subsequently,a representative performance evaluation is presented,based on the reported oxygen electrodes used in rechargeable metal-air battery applications.By focusing on these key areas,the review outlines the current challenges and future prospects for the development of bifunctional oxygen electrocatalysts,aiming to guide the design of high-performance bifunctional electrocatalysts and to elucidate the underlying mechanisms involved. 展开更多
关键词 oxygen reduction reaction oxygen evolution reaction Design strategy MODIFICATION Rechargeable metal-air battery
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Targeting cancer cell mitochondria with a multivalent source of singlet oxygen
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作者 Wanwan Wang Lei Wang +2 位作者 Rensong Sun Shoucai Yan Engin U.Akkaya 《Smart Molecules》 2026年第1期118-126,共9页
Naphthalene,anthracene and pyridone endoperoxides are known to thermally release singlet oxygen.However,in the cycloreversion reaction,singlet oxygen is produced stoichiometrically;therefore,multiple singlet oxygen re... Naphthalene,anthracene and pyridone endoperoxides are known to thermally release singlet oxygen.However,in the cycloreversion reaction,singlet oxygen is produced stoichiometrically;therefore,multiple singlet oxygen releasing modules are expected to be very useful in inducing apoptosis of cancer cells.Herein,we present a potential therapeutic agent presenting three-pyridone endoperoxide modules and a mitochondria targeting group.Compared to previously reported pyridone-based monofunctional endoperoxides,the triple endoperoxide is highly effective as evidenced by assays and fluorescence microscopy. 展开更多
关键词 cancer ENDOPEROXIDES mitochondria targeting PDT singlet oxygen
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Boosting carrier utilization in Pr^(3+)-doped long-afterglow photocatalysts through oxygen vacancy engineering for enhanced photo-Fenton degradation
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作者 Xiaoxuan Fan Yonggui Zheng +8 位作者 Ran Tao Lirong Xu Shanshan Jiang Hainan Li Tianya Tan Shuo Cao Xuemei Lu Kexin Wang Jiwei Wang 《Journal of Rare Earths》 2026年第3期791-801,I0003,共12页
Long-afterglow photocatalytic technology offers promising potential fo r all-weather pollutant treatment,yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions.T... Long-afterglow photocatalytic technology offers promising potential fo r all-weather pollutant treatment,yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions.To address this,we developed a Pr^(3+)-doped Ca_(2)Al_(2)SiO_(7)(CASO)photocatalyst enriched with oxygen vacancies(V_(O)).The introduction of oxygen vacancies significantly increases trap concentration,enhancing both the intensity and du ration of the afterglow emission.A persulfate-assisted photo-Fenton system was designed based on V_(O)-CASO:Pr^(3+)enabling the self-activated degradation of tetracycline hydrochloride(TC)under ultraviolet afterglow.The photo-Fenton reaction consumes excess holes accumulated during the afterglow process,improving carrier utilization efficiency and mitigating rapid recombination.Additionally,persulfate addition can enrich reactive species and facilitate the Fe^(2+)/Fe^(3+)cycle.Benefiting from these synergistic effects,V_(O)-CASO:Pr^(3+)has achieved 75%TC degradation within1 h,significantly outperforming traditional systems.This study provides a new strategy for enhancing long-afterglow photocatalytic performance,paving the way for sustainable pollutant degradation technologies. 展开更多
关键词 Long afterglow PHOTOCATALYTIC PHOSPHORS FENTON oxygen vacancy Rare earths
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Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells
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作者 Zijie Lin Qing Li 《Chinese Chemical Letters》 2026年第1期7-9,共3页
Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and effic... Covalent organic framework ionomers enable synergistic efficient transport of protons and oxygen in medium-temperature proton exchange membrane fuel cells Proton exchange membrane fuel cells(PEMFCs),as clean and efficient energy technologies,are constrained in their performance enhancement by the sluggish oxygen reduction reaction(ORR)kinetics at the cathode,anode CO poisoning(e.g.,from methanol crossover)and intricate water management dilemmas[1]. 展开更多
关键词 covalent organic framework ionomers proton exchange membrane fuel cells pemfcs proton exchange membrane fuel cells sluggish oxygen reduction reaction orr kinetics PROTONS water management dilemmas oxygen
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Rationally designed nickel-cobalt oxide/sulfide heterostructure for high-performance oxygen evolution reaction and anion exchange membrane water electrolysis
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作者 Hyeonji Kwon Hyeongseok Seo +3 位作者 Siyeon Kang Sang Eun Shim Kyeongseok Min Sung-Hyeon Baeck 《Journal of Energy Chemistry》 2026年第1期955-966,I0021,共13页
To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,w... To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis. 展开更多
关键词 AEMWE oxygen evolution reaction Transition metal HETEROINTERFACE Hollow structure
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