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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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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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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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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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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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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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A low-cost TiNb alloy with high strength for orthopedic implants with low modulus tuned by oxygen concentration
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作者 LOU Jia TANG Xin-dong +2 位作者 DU Chang-hai LI Dong-yang LI Yi-min 《Journal of Central South University》 2026年第1期78-89,共12页
Hard tissue repair materials that balance high strength with low modulus are highly promising,representing a transformative focus in applied biomaterials research.In this study,Ti-Nb alloys with high performance are p... Hard tissue repair materials that balance high strength with low modulus are highly promising,representing a transformative focus in applied biomaterials research.In this study,Ti-Nb alloys with high performance are prepared by a low-cost process for orthopedic applications.Phase composition,modulus,compressive strength and recovery properties are effectively manipulated by tailoring trace amounts of interstitial oxygen.With increasing oxygen concentration in sintered Ti-Nb alloys,theβ(body centered cubic)phase was stabilized due to the lattice distortion.The elastic modulus declined from 91 to 24 GPa.The compressive strength slightly decreased from 1595 to 1404 MPa and yield strength increased from 760 to 904 MPa.Additionally,the recovery properties were enhanced by the interstitial oxygen as a shape memory alloy.The utilization of trace oxygen serves to modulate the thermoelastic martensitic transformation in Ti-Nb alloys,thereby obtaining appropriate mechanical properties.A notable reduction in modulus is achieved while maintaining high strength,which facilitates the development of orthopedic implants capable of withstanding more complex forces. 展开更多
关键词 TITANIUM TiNb low modulus oxygen recovery properties XRD refinement
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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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Optimizing the RuCo Ratio for More Efficient and Durable Oxygen Reduction in Acidic Media
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作者 WEI Mingrui ZHANG Shuai +1 位作者 HUANG Shuo WANG Chao 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期25-32,共8页
The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a serie... The development of Pt-free catalysts for the oxygen reduction reaction(ORR)is a great issue for meeting the cost challenges of proton exchange membrane fuel cells(PEMFCs)in commercial applications.In this work,a series of RuCo/C catalysts were synthesized by NaBH4 reduction method under the premise that the total metal mass percentage was 20%.X-ray diffraction(XRD)patterns and scanning electron microscopy(SEM)confirmed the formation of single-phase nanoparticles with an average size of 33 nm.Cyclic voltammograms(CV)and linear sweep voltammograms(LSV)tests indicated that RuCo(2:1)/C catalyst had the optimal ORR properties.Additionally,the RuCo(2:1)/C catalyst remarkably sustained 98.1% of its activity even after 3000 cycles,surpassing the performance of Pt/C(84.8%).Analysis of the elemental state of the catalyst surface after cycling using X-ray photoelectron spectroscopy(XPS)revealed that the Ru^(0) percentage of RuCo(2:1)/C decreased by 2.2%(from 66.3% to 64.1%),while the Pt^(0) percentage of Pt/C decreased by 7.1%(from 53.3% to 46.2%).It is suggested that the synergy between Ru and Co holds the potential to pave the way for future low-cost and highly stable ORR catalysts,offering significant promise in the context of PEMFCs. 展开更多
关键词 ELECTROCATALYSIS oxygen reduction DURABILITY RuCo/C fuel cell
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Growth of Ce-doped NiCo-LDHs on tin dioxide-modified nickel foam as oxygen evolution reaction catalyst electrode
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作者 Zhongjie Song Nannan Zhang +3 位作者 Jun Yu Huiyu Sun Zhengying Wu Yukou Du 《Chinese Chemical Letters》 2026年第1期689-695,共7页
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes... Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer. 展开更多
关键词 oxygen evolution reaction HETEROSTRUCTURE DOPING Conductive layer
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Oxygenation-driven multimodal photoacoustic/ultrasonic imaging enhances evaluation of enthesitis disease activity in psoriatic arthritis
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作者 Rui Zhang Fan Yang +8 位作者 Chenyang Zhao Ming Wang Yan Zhang Fang Yang Lei Zhu Jianchu Li Yuxin Jiang Xiaomei Leng Meng Yang 《Journal of Innovative Optical Health Sciences》 2026年第1期126-138,共13页
Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation... Conventional ultrasound(US)evaluation of enthesitis in psoriatic arthritis(PsA)is limited by its inability to quantify metabolic alterations such as hypoxia,a key driver of disease activity.We introduce an oxygenation-integrated multimodal photoacoustic/ultrasound(PA/US)imaging framework designed to quantify entheseal oxygen saturation(SO_(2))for assessing entheseal disease activity in PsA.In this cross-sectional study,25 PsA patients underwent bilateral PA/US imaging of 12 entheses,where ultrasound lesions were scored using the Outcome Measures in Rheumatology scoring system,and PA-derived SO_(2) levels,quantified via dual-wavelength PA imaging,were classified into hyperoxia or hypoxia groups using k-means clustering.This approach provides metabolic insights complementary to conventional ultrasonic assessment.A composite score integrating hypoxia with US parameters was validated against clinical disease activity indices(Disease Activity Score 28-C-reactive protein,DAS28-CRP;Disease Activity Index for Psoriatic Arthritis,DAPSA).Among 300 entheses,103(34.3%)exhibited PA positivity,with 40(38.8%)classified as hypoxia.Hypoxia scores independently predicted DAS28-CRP(β=0.618,p=0.001)and DAPSA(β=0.612,p<0:001).The hypoxia-optimized PAUS score demonstrated superior correlation with disease activity indices compared to conventional US(DAS28-CRP:r=0.615,p=0.001 versus r=0.474,p=0.017;DAPSA:r=0.743,p<0:001 versus r=0.567,p=0.003),alongside superior diagnostic accuracy for minimal disease activity(area under the curve,AUC 0.776 versus 0.614,p=0.008)and low disease activity(AUC 0.853 versus 0.772,p=0.009).This multimodal scoring system enhances the stratification of PsA disease activity by providing unique metabolic insights,offering a potential tool for therapeutic monitoring and guiding treat-to-target strategies. 展开更多
关键词 Photoacoustic imaging oxygen saturation ENTHESIS disease activity evaluation
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Human development and gender inequality are associated with cardiorespiratory fitness:A global systematic review of VO_(2peak)
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作者 Nicolas J.Pillon Joaquin Ortiz de Zevallos +1 位作者 Juleen R.Zierath Barbara E.Ainsworth 《Journal of Sport and Health Science》 2026年第3期27-36,共10页
Background:Cardiorespiratory fitness(CRF)is a powerful predictor of mortality and chronic disease risk,yet global patterns and determinants of CRF remain poorly defined,particularly in females and underrepresented pop... Background:Cardiorespiratory fitness(CRF)is a powerful predictor of mortality and chronic disease risk,yet global patterns and determinants of CRF remain poorly defined,particularly in females and underrepresented populations.We conducted a systematic review and quantitative synthesis of directly measured peak oxygen uptake(VO_(2peak))internationally and examined its association with human development and gender ine quality.Methods:Studies were eligible if VO_(2peak)was assessed via direct gas analysis during maximal exercise testing,and if the countries had scores for the Human Development Index(HDI)and Gender Inequality Index(GII).Studies were identified through MEDLINE/PubMed,Embase,CINAHL,and Web of Science.Risks of bias were assessed by an adaptation of the Newcastle-Ottawa Scale.Multivariable linear regression models examined associations between VO_(2peak),age,sex,exercise modality,HDI,GII,and study year.Results:Data included 95 studies from 24 countries with HDI and GII scores,comprising 119,435 adults(42%females)with VO_(2peak)assessed via direct gas analysis during maximal exercise testing.The risk of bias was low.VO_(2peak)was positively associated with HDI(β=14.1)and negatively associated with GII(β=-3.6).Slightly stronger associations were observed in females than males(HDI:β=18.9 vs.β=13.9,GII:β=-4.6vs.β=-3.6).Young females in middle-HDI countries had higher VO_(2peak)than those in low-HDI countries(31.2mL/kg/min vs.28.5 mL/kg/min),with limited additional gams in high-HDI contexts.VO_(2peak)decreased with higher gender inequality,with the largest disparities observed in young females between high-and low-GII countries(26.3 mL/kg/min vs.32.8 mL/kg/min).Conclusion:Global variation in CRF is tied to national levels of human development and gender equality.These findings support prioritizing structural and policy-level interventions that address social and gender disparities in physical activity access and health promotion.Studies from countries with lower HDI and information on ethnicity and socioeconomic status will bridge crucial gaps in understanding factors involved in global CRF levels. 展开更多
关键词 Human development index Gender inequality index oxygen uptake INTERNATIONAL Physical activity
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Fe-loaded S,N co-doped carbon catalyst for oxygen reduction reaction with enhanced electrocatalytic activity and durability
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作者 Shengzhi He Chunwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期315-321,共7页
Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-... Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-doped carbon(Fe/SNC)via in situ incorporation of 2-aminothiazole molecules into zeolitic imidazolate framework-8(ZIF-8)through coordination between metal ions and organic ligands.Sulfur and nitrogen doping in carbon supports effectively modulates the electronic structure of the catalyst,increases the Brunauer-Emmett-Teller surface area,and exposes more Fe-N_(x)active centers.Fe-loaded,S and N co-doped carbon with Fe/S molar ratio of 1:10(Fe/SNC-10)exhibits a half-wave potential of 0.902 V vs.RHE.After 5000 cycles of cyclic voltammetry,its half-wave potential decreases by only 20 mV vs.RHE,indicating excellent stability.Due to sulfur s lower electronegativity,the electronic structure of the Fe-N_(x)active center is modulated.Additionally,the larger atomic radius of sulfur introduces defects into the carbon support.As a result,Fe/SNC-10 demonstrates superior ORR activity and stability in alkaline solution compared with Fe-loaded N-doped carbon(Fe/NC).Furthermore,the zinc-air battery assembled with the Fe/SNC-10 catalyst shows enhanced performance relative to those assembled with Fe/NC and Pt/C catalysts.This work offers a novel design strategy for advanced energy storage and conversion applications. 展开更多
关键词 zinc-air batteries oxygen reduction reaction iron-loaded nitrogen-doped carbon sulfur-doping
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Heteroatom‑Coordinated Fe–N_(4) Catalysts for Enhanced Oxygen Reduction in Alkaline Seawater Zinc‑Air Batteries
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作者 Wenhan Fang Kailong Xu +5 位作者 Xinlei Wang Yuanhang Zhu Xiuting Li Hui Liu Danlei Li Jun Wu 《Nano-Micro Letters》 2026年第3期554-568,共15页
Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction... Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction(ORR)and chlorideinduced degradation over conventional catalysts.In this study,we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N_(4) single-atom seawater catalyst materials(Cl–Fe–N_(4) and S–Fe–N_(4)).X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure.Systematic evaluation of catalytic activities revealed that compared with S–Fe–N_(4),Cl–Fe–N_(4) exhibits smaller electrochemical active surface area and specific surface area,yet demonstrates higher limiting current density(5.8 mA cm^(−2)).The assembled zinc-air batteries using Cl–Fe–N_(4) showed superior power density(187.7 mW cm^(−2) at 245.1 mA cm^(−2)),indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity.Moreover,Cl–Fe–N_(4) demonstrates stronger Cl−poisoning resistance in seawater environments.Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability.Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom,leading to more active reaction intermediates and increased electron density of Fe single sites,thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity. 展开更多
关键词 Single-atom catalyst Zinc-air battery Seawater catalyst oxygen reduction reaction
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