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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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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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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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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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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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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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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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Donor regulation of donor-acceptor MOF toward more accessible photocatalyst for effective singlet oxygen-based photooxidation
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作者 Kai Wang Chang-Tai Li +6 位作者 Qingfang Mu Guo-Lei Zhang Mei-Hui Yu Jijie Zhang Weijie Hua Ze Chang Xian-He Bu 《Science China Chemistry》 2026年第2期761-767,共7页
Singlet oxygen(^(1)O_(2))is recognized as one of the most effective and selective oxygen agents.However,the explorative study of photocatalysts(PCs)for effective ^(1)O_(2)-based photocatalytic oxidation remains challe... Singlet oxygen(^(1)O_(2))is recognized as one of the most effective and selective oxygen agents.However,the explorative study of photocatalysts(PCs)for effective ^(1)O_(2)-based photocatalytic oxidation remains challenging and critical.In this study,a novel donor-acceptor metal-organic framework(D-A MOF)has been developed by engineering the D-A system,which was then evaluated as a photocatalyst for ^(1)O_(2)-based oxidation.By regulating the donor component of the D-A systematic framework,the MOF(B1)exhibits delayed fluorescence(DF)behavior with a reduced singlet-triplet gap.Given the significantly improved electron transfer behavior in combination with an efficient energy transfer process,the optimal B1 demonstrates remarkable activity toward ^(1)O_(2)generation under suitable photoexcitation conditions.Therefore,it can be utilized for the photocatalytic oxidation of 1,5-dioxynaphthalene(1,5-DHN)to Juglone,achieving the highest yield(conversion>99%at 25℃ in 30 min)and selectivity among all previously reported MOF photocatalysts. 展开更多
关键词 donor-acceptor MOF triplet exciton PHOTOCATALYST energy transfer singlet oxygen
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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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Characteristics and driving factors of oceanic oxygen minimum zone(OMZ)in the context of global change
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作者 Jun MA Jinming SONG +4 位作者 Xuegang LI Huamao YUAN Liqin DUAN Jiajia DAI Lilian WEN 《Science China Earth Sciences》 2026年第2期478-490,共13页
As a water layer with significantly reduced dissolved oxygen(DO)in the ocean,the oxygen minimum zone(OMZ)plays a crucial role in regulating marine organism distribution,global material cycles,and climate change.Based ... As a water layer with significantly reduced dissolved oxygen(DO)in the ocean,the oxygen minimum zone(OMZ)plays a crucial role in regulating marine organism distribution,global material cycles,and climate change.Based on a systematic review of recent studies on OMZ,this paper summarizes the DO thresholds,structural characteristics,distribution patterns,formation and maintenance mechanisms,and driving factors of OMZ in the ocean in the context of global change.The DO thresholds of OMZ typically range from 20 to 100μmol L^(-1).Specifically,the threshold is mostly 20μmol L^(-1) in regions with intense OMZ,such as the Eastern Pacific and Northern Indian Oceans,while it is mostly 100μmol L^(-1) in regions with mild OMZ,including the Western Pacific and Atlantic.In terms of structure,the OMZ is mainly composed of three parts:the upper oxycline,the lower oxycline,and the OMZ core.Significant differences exist in the horizontal and vertical distributions of OMZ across different regions.OMZ is mainly concentrated in tropical and subtropical regions,with the widest distribution in the eastern tropical North Pacific.The upper boundary of OMZ is shallower(50-150 m)in significantly affected regions,whereas it is below 200 m in less affected regions.The formation of OMZ is governed by the continuous consumption of DO in the ocean interior,and the water exchange restriction caused by seawater stratification,whereas the maintenance of the hypoxic state of OMZ relies on two positive feedbacks:increased microbial oxygen consumption due to reduced animal feeding,and increased oxygen consumption by anaerobic metabolic products.In the context of global change,rising temperature is the main driver of OMZ expansion,reducing O_(2) solubility,increasing respiration and decomposition rates,and enhancing seawater stratification.Additionally,the structure and evolution of OMZ is also profoundly affected by ocean circulation such as thermohaline circulation,wind-driven circulation,and upwelling,as well as changes in wind stress,mesoscale eddies and freshwater flux.Future research should focus on establishing OMZ gradient thresholds and classification criteria based on the law of deoxygenation,improving the systematic understanding of the temporal and spatial variations of OMZ,and continuously strengthening studies on OMZ in the Western Pacific. 展开更多
关键词 oxygen minimum zone(OMZ) HYPOXIA OCEAN Basic characteristics
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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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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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Nursing Care of a Child with Acute Fulminant Myocarditis Treated by Extracorporeal Membrane Oxygenation
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作者 Yuhua TONG Rong WANG Baoyi YANG 《Medicinal Plant》 2026年第1期43-45,共3页
This paper summarizes the nursing experience of a child with acute fulminant myocarditis.Key nursing measures include establishing a multidisciplinary team to jointly formulate diagnosis and treatment plans;implementi... This paper summarizes the nursing experience of a child with acute fulminant myocarditis.Key nursing measures include establishing a multidisciplinary team to jointly formulate diagnosis and treatment plans;implementing refined volume management,anticoagulation management,and ventilator management during extracorporeal membrane oxygenation;providing personalized nutritional support for the child;and strengthening the prevention and management of complications.After active treatment and nursing care,the child recovered well and was successfully transferred out of the intensive care unit. 展开更多
关键词 Extracorporeal membrane oxygenation Acute fulminant myocarditis Nursing care
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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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Bacteria outer membrane-based oxygen gels alleviate tumor hypoxia for enhanced systemic immune response to radiotherapy
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作者 Deyuan Zheng Junhong Yao +7 位作者 Haiheng Xu Shuqin Xiong Qingsong Ye Yiyun Chen Chuan Zhao Min Zhang Xuehui Rui Jinhui Wu 《Science China Materials》 2026年第3期1729-1740,共12页
Radiotherapy(RT)is considered a standard cancer treatment that directly kills tumor cells and promotes a systemic immune response.However,RT may also lead to tumor hypoxia,which further inhibits the antigen-presenting... Radiotherapy(RT)is considered a standard cancer treatment that directly kills tumor cells and promotes a systemic immune response.However,RT may also lead to tumor hypoxia,which further inhibits the antigen-presenting function of dendritic cells(DCs)and thereby weakens the systemic anti-tumor immune response induced by radiotherapy.In this study,the oxygen-loaded in situ gels carrying bacterial outer membrane(MOGel)were synthesized.As the gels slowly degraded,oxygen was gradually released to alleviate tumor hypoxia.The released bacterial outer membrane(OM)continuously activated DCs,enhancing their antigenpresenting capability.The results demonstrated that MOGel combined with RT induced the strongest tumor cell apoptosis in vitro and achieved a 80%tumor suppression rate in a colon cancer orthotopic model.Importantly,MOGel+RT induced an enhanced abscopal effect,and hypoxia and enhanced DCs activation contributed to the systemic immune response.Thus,OM-based oxygen gels may offer a novel strategy for enhancing the systemic immune response to RT. 展开更多
关键词 bacteria outer membrane oxygen gels tumor hypoxia RADIOTHERAPY systemic immune response
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue Functional near-infrared spectroscopy
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Effect of calcination temperature on interlayer spacing and oxygen vacancies concentration of NaCu_(0.2)Fe_(0.3)Mn_(0.5)O_(2) layered materials for sodium-ion batteries
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作者 Bo-wen XU Da ZHANG +4 位作者 Xuan-tian FENG Sheng-ping HOU Peng DONG Dong-feng XUE Feng LIANG 《Transactions of Nonferrous Metals Society of China》 2026年第2期600-613,共14页
NaCu_(0.2)Fe_(0.3)Mn_(0.5)O_(2) (NCFM) cathode material was synthesized using a simple solid-state reaction, and the effect of calcination temperature on its interlayer spacing and oxygen vacancies concentration was i... NaCu_(0.2)Fe_(0.3)Mn_(0.5)O_(2) (NCFM) cathode material was synthesized using a simple solid-state reaction, and the effect of calcination temperature on its interlayer spacing and oxygen vacancies concentration was investigated. Through electrochemical testing and material characterizations, higher calcination temperatures increase the electrostatic repulsion between oxygen atoms in adjacent layers, resulting in an expansion of Na layer spacing. This structural change enhances the diffusion kinetics of Na^(+), thereby significantly improving the rate performance of NCFM. Furthermore, elevated calcination temperatures facilitate the reduction of oxygen vacancies, leading to improved crystallinity. This enhancement in crystallinity mitigates structural strain during phase transitions, contributing to improved cyclic stability. Consequently, the optimized NCFM shows an initial discharge specific capacity of 143.3 mA·h/g at 0.1C, with a capacity retention rate of 79.28% after 100 cycles at 1C. 展开更多
关键词 sodium ion batteries calcination temperature control interlayer spacing oxygen vacancies electrochemical performance
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