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Distortions and Deformations of Metaled Meso-Substituted and Unsubstituted Porphyrins and Derivatives in Crystal Structures 被引量:1
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作者 Philippe V. Tsalu Tharcisse O. Monama +7 位作者 Hilaire V. Mambo Dorothée D. Tshilanda Pius T. Mpiana Bodrique M. Nsimba Virima Mudogo Pitchou N. Bokolombe Damien S. T. Tshibangu Zephyrin G. Yav 《Crystal Structure Theory and Applications》 2016年第1期1-15,共15页
Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were reviewed to show how far the meso-substitution by any functional group and the insertion of ... Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were reviewed to show how far the meso-substitution by any functional group and the insertion of metal in the porphyrins core macrocycle may affect the geometry. The analysis of twists and angles has shown two kinds of distortions: external [T(C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-X<sup>n</sup>) and T(C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-C<sup>α</sup>)] and internal [T(N<sup>m</sup>-C<sup>α</sup>-C<sup>meso</sup>-X<sup>n</sup>) and T(N<sup>n</sup>-C<sup>α</sup>-C<sup>meso</sup>-C<sup>α</sup>)] with averages of [+6&deg;and –6&deg;] and [–5&deg;and +5&deg;], respectively. In the meso-substituted case, the external and internal twists C<sup>β</sup>-C<sup>α</sup>-C<sup>meso</sup>-X and N-C<sup>α</sup>-C<sup>meso</sup>-X, respectively are oppositely orientated. Similar effect is observed in meso-unsubstituted of C<sup>β</sup>-C<sup>α</sup>- C<sup>meso</sup>-H and N-C<sup>α</sup>-C<sup>meso</sup>-H. However, the external distortions are more significant than internal. Considering the same order, the limit of distortions is [97&deg;and 132&deg;(–48&deg;)] for external and [91&deg;(–89&deg;) and 52&deg;] for internal. In the two cases, the substituents have opposite directions of distortions. The meso-substituted porphyrins have a high limit of twisting than usubstituted one, depending of the weight of substituents. The average of the bond angular deformations is 168&deg;, almost planar. However, the limit of angular deformation is 94&deg;. 展开更多
关键词 metaled Meso-Substituted and Unsubstituted Porphyrins and Derivates Crystals Structures Distortions and Bonds Angular Deformations
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Detection of the Oscillation Marks on Casting Slabs Using Magnetic Flux Variation and the Nonexcitation Method
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作者 FENG Kaibin LIU Runcong +3 位作者 LI Silong WU Yunfei NA Xianzhao WANG Xiaodong 《材料导报》 北大核心 2026年第1期149-158,共10页
T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection met... T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity. 展开更多
关键词 oscillation marks REMANENCE metal magnetic memory near surface defects nondestructive testing(NDT)
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Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
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作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin D deficiency
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Melatonin:a key player in alleviating heavy metal stress in plants―current insights and future directions
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作者 Wenhan Dong 《Horticultural Plant Journal》 2026年第1期36-48,共13页
Heavy metal(HM)contamination severely impacts global agricultural production.HMs toxicity effectively damaged the physiological functions such as imbalanced redox homeostasis,altered antioxidant enzyme activity,damage... Heavy metal(HM)contamination severely impacts global agricultural production.HMs toxicity effectively damaged the physiological functions such as imbalanced redox homeostasis,altered antioxidant enzyme activity,damage root system architecture,hindered photosynthetic apparatus,cellular toxicity,restricted mineral accumulation,and changed the metabolite production.Using phytohormones may be a successful strategy for enhancing and stimulating plant tolerance to HMs toxicity without affecting the environment.Melatonin(MT),a novel plant growth regulator,and powerful antioxidant molecule,enhances plant resilience to HMs stress by enhancing seedling growth,protecting the photosynthetic system,increasing nutritional status,balanced redox homeostasis,and restricting HMs accumulation from root to shoot.In addition,MT enhances the activity of antioxidant enzymes and triggers the ascorbate-glutathione(AsA-GSH)cycle,which helps remove excessive ROS.MT improves RuBisCO activity to improve photosynthesis and reduce the breakdown of chlorophyll.To identify future research needs,it is crucial to understand the comprehensive and intricate regulatory mechanisms of exogenous and endogenous MT-mediated reduction of heavy metal toxicity in plants.Melatonin has several functions,and this review sheds light on those functions and the molecular processes by which it alleviates HMs toxicity.More research is needed to fully understand how melatonin affects plant tolerance to heavy metals stress. 展开更多
关键词 MELATONIN Heavy metals PHOTOSYNTHESIS Cell wall Cellular function Stress management
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In-built intermolecular hydrogen bonds enabling stable interfacial chemistry for all-solid-state Li metal batteries
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作者 Teng Xu Mengyan Gu +6 位作者 Qin Sun Zhiyuan Guo Zijun Li Mei Yang Qiuying Xia Yiren Zhong Hui Xia 《Nano Research》 2026年第1期1350-1359,共10页
The vip-host chemistry in polymer electrolytes plays a crucial role for all-solid-state Li metal batteries,where the stable operation of such batteries heavily relies on high ion conductivity,strong mechanical prope... The vip-host chemistry in polymer electrolytes plays a crucial role for all-solid-state Li metal batteries,where the stable operation of such batteries heavily relies on high ion conductivity,strong mechanical properties,and stable interfaces of the electrolyte.While traditional ceramic fillers can boost ion conductivity,they fail to improve interfacial stability.In this study,we introduce intermolecular hydrogen bonding into a polyethylene oxide(PEO)-based polymer electrolyte through the incorporation of metal organic framework(MOF)and lithium nitrate additives.The hydrogen on the PEO chain is found to be tightly interacted with the oxygen nodes of UiO-66 MOF and nitrate anions,creating a cross-linked framework that reduces the crystallinity of the PEO and enhances the integrity of composite.This interaction induces a beneficial Li3N and LiF-rich solid electrolyte interphase,ensuring 2000 h of stable lithium metal operation without short-circuits.The strong polysulfide adsorption enables compatibility with high-capacity sulfur cathodes,resulting in solidstate Li-S batteries that can achieve a high capacity of 913.8 mAh·g^(-1)and exhibit stable cycling performance.This work demonstrates the deep understanding of vip-host chemistry in polymer electrolytes and their potential in developing energy-dense solid-state Li metal batteries. 展开更多
关键词 solid-state Li metal batteries polyethylene oxide(PEO)electrolyte metal organic frameworks(MOFs) hydrogen bonds
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Preparation of large-area graphene film with oriented or unoriented structure by controlling self-assembly for lithium metal batteries
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作者 Tengfei Bian Qi Zhang +4 位作者 Xiaobing Wang Yong Zhong Feng Bai Jie Ju Yong Zhao 《Nano Research》 2026年第1期633-643,共11页
Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered asse... Large-area graphene films with defined uniformity,thickness and morphology are crucial for their applications in optoelectronic and photothermal devices.Herein,we demonstrate that oriented arrangement and ordered assembly of graphene oxide(GO)nanosheets in solution films can be realized to obtain the high-quality and large-area reduced GO(rGO)films.The key to the success of this process primarily lies in the control of GO solution shear force direction with array capillaries,achieving oriented arrangement of GO nanosheets in the solution film.Secondly,the control of GO nanosheet concentration and solution viscosity during solvent evaporation of solution film is key to achieve the ordered and disordered assembly of GO,featuring the smooth and wrinkled structure rGO films,respectively.Subsequently,the resultant smooth rGO film with ordered assembly exhibits excellent thermal conductivity and electronic conductivity(over 1800 S·cm-1).Meanwhile,the wrinkled rGO film with disordered assembly can be used as a coating layer on Al current collectors,demonstrating anticorrosion properties and enhanced material adhesive stability.As a result,with such collectors,the high-voltage Li//NCM811 batteries show a 6-fold increase in cycle stability,and the lithium-sulfur batteries with high sulfur loading show a 3-fold increase in cycle stability. 展开更多
关键词 GRAPHENE current collector electronic conductivity SELF-ASSEMBLY lithium metal batteries
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Nanoparticle assisted phytoremediation:An eco-friendly approach for removal of heavy metals from the environment
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作者 Sakshi Sharma Ritika Dadhwal Ritesh Banerjee 《Journal of Environmental Sciences》 2026年第1期705-720,共16页
The surge in environmental pollution in recent years driven by numerous pollutants has necessitated the search for efficient removal methods.Phytoremediation is an eco-friendly technique that provides multiple benefit... The surge in environmental pollution in recent years driven by numerous pollutants has necessitated the search for efficient removal methods.Phytoremediation is an eco-friendly technique that provides multiple benefits over conventional methods of removing contaminants.Despite the numerous benefits of this technique,it has certain limitations that can be addressed by incorporating nanoparticles to improve its effectiveness.This review paper aims to explore the impact of heavy metal pollution on plants and human health.It highlights the role and mechanism of nanoparticles in enhancing phytoremediation,their application in the detection of heavy metals,and the strategies for the safe disposal of phytoremediation biomass.Biosynthesized nanoparticles are eco-friendly and non-toxic,with applications in biomedical and environmental fields.Nanoparticles can be used in the form of nano biosensors like smartphone-operated wireless sensors made from Cinnamomum camphora,enabling efficient detection of heavy metal ions.According to the studies,nanoparticles remove 80%–97%of heavy metals by various methods like reduction,precipitation,adsorption,etc.The phytoremediation biomass disposal can be done by heat treatment,phytomining,and microbial treatment with some modifications to further enhance their results.Phytoremediation is an environmentally friendly technique but requires further research and integration with biomass energy production to overcome scalability challenges and ensure safe biomass disposal. 展开更多
关键词 PHYTOREMEDIATION Heavy metals Nanoparticles Environmental contamination Postharvest biomass management
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Solar-Driven Redox Reactions with Metal Halide Perovskites Heterogeneous Structures
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作者 Qing Guo Jin‑Dan Zhang +1 位作者 Jian Li Xiyuan Feng 《Nano-Micro Letters》 2026年第2期337-367,共31页
Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks... Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks such as inferior stability,severe charge-carrier recombination,and limited active sites.Heterojunctions have recently been widely constructed to improve light absorption,passivate surface for enhanced stability,and promote charge-carrier dynamics of MHPs.However,little attention has been paid to the review of MHPs-based heterojunctions for photocatalytic redox reactions.Here,recent advances of MHPs-based heterojunctions for photocatalytic redox reactions are highlighted.The structure,synthesis,and photophysical properties of MHPs-based heterojunctions are first introduced,including basic principles,categories(such as Schottky junction,type-I,type-II,Z-scheme,and S-scheme junction),and synthesis strategies.MHPs-based heterojunctions for photocatalytic redox reactions are then reviewed in four categories:H2evolution,CO_(2)reduction,pollutant degradation,and organic synthesis.The challenges and prospects in solar-light-driven redox reactions with MHPs-based heterojunctions in the future are finally discussed. 展开更多
关键词 Metal halide perovskite HETEROJUNCTION Redox reaction Solar-to-chemical conversion
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Biodegradation performance of azo dyes based on Fe-Mn@C dual-template molecularly imprinted sensor
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作者 Qikai Fu Deliang Guo +2 位作者 Xiaoyu Zhang Xiongfang An Xiaolin Xu 《Journal of Environmental Sciences》 2026年第1期546-554,共9页
The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template ... The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template molec-ularly imprinted sensor(DTMIP/Fe-Mn@C)for iron manganese metal nanomaterials,prepared Fe-Mn@C com-posite materials by a one pot method were coated on the surface of glassy carbon electrodes and covered with molecularly imprinted membranes through electropolymerization and elution methods,achieving real-time de-tection of specific intermediate products 2-methylbutyric acid(2-MBA)and 3-methylbutyric acid(3-MBA)de-graded by azo dyes.In order to determine the detection sensitivity and intensity range of the sensor,optimization experiments were conducted on various parameters that affect the detection performance,such as the type of func-tional monomer and its composition ratio with the template molecule,detection time window,environmental pH value,etc.Finally,o-Phenylenediamine was determined as the functional monomer,with a molar ratio of 1:1:6 to the template molecules 2-MBA and 3-MBA.Electrochemical testing was conducted in a neutral environment with an incubation time of 5 min and pH=7.The results indicate that the sensor has a relatively wide detection range,high sensitivity,obvious recognition features,and excellent stability for 2-MBA and 3-MBA.This new dual template molecularly imprinted sensor can quickly and accurately determine the safety of highly toxic interme-diates in the degradation process of aromatic organic pollutants,providing a theoretical basis and application potential for trace detection and real-time monitoring. 展开更多
关键词 Azo dyes Microbial degradation Metal nanomaterials Dual-template molecular Degradation process
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Performance and Microscopic Influence Mechanism of Solidified Cadmium Contaminated Soil by Rice Husk Ash Based Geopolymer
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作者 CHEN Wei HAN Jianhong +5 位作者 YU Hongbao XU Hong WANG Ying FAN Wenxiao ZHAO Lina LIU Peijie 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期171-178,共8页
In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadm... In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadmium contaminated soil.The main physical and chemical properties of rice husk ash were clarified by SEM,XRF and X-ray diffraction.The unconfined compressive strength test and toxicity leaching test were carried out on the modified soil.Combined with FTIR and TG micro-level,the solidification mechanism of rice husk ash-based geopolymer solidified cadmium contaminated soil was discussed.The results show that the strength of geopolymer modified soil is significantly higher than that of plain soil,and the unconfined compressive strength at 7 d age is 4.2 times that of plain soil.The strength of modified soil with different dosage of geopolymer at 28 d age is about 36% to 40% higher than that of modified soil at 7 d age.Geopolymer has a significant effect on the leaching of heavy metals in contaminated soil.When the cadmium content is 100 mg/kg,it meets the standard limit.In the process of complex depolymerization-condensation reaction,on the one hand,geopolymers are cemented and agglomerated to form a complex spatial structure,which affects the macro and micro characteristics of soil.On the other hand,it has significant adsorption,precipitation and replacement effects on heavy metal ions in soil,showing good strength and low heavy metal leaching toxicity. 展开更多
关键词 rice husk ash alkali excitation heavy metals curing mechanism
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Heavy metal risks and policy analysis on using industrial waste salts for making value-added snow-melting agents
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作者 Yubiao Ma Jiaxin Yin +2 位作者 Yunfei Wang Lei Wang Jianxin Zhu 《Journal of Environmental Sciences》 2026年第1期756-766,共11页
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po... Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management. 展开更多
关键词 Snow-melting agent Heavy metals Industrial waste salts recycled Comparative analysis
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Metal(loid)accumulation and foliar physiological responses in Oryza sativa L.induced by PM1 exposure from various emission sources
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作者 Meixuan Fang Yue Yang +4 位作者 Baofeng Zhang Yingluo Chen Jingdong Mao Liping Lou Qi Lin 《Journal of Environmental Sciences》 2026年第1期585-595,共11页
Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in... Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in submicron-scale particulates(PM1),this study established a PM1 exposure system to examine airborne metal(loid)accu-mulation and foliar physiological responses in Oryza sativa L.The results showed that the concentrations of Cu,Zn,As,Pb,and Cd in the leaves and grains were influenced not only by the airborne metal(loid)levels but also by the specific nature of the PM1 particles.The quantitative model for PM1-associated Pb entry into leaf tissue indicated that foliar Pb accumulation was primarily driven by particle adhesion,followed by hydrophilic pene-tration and trans-stomatal liquid film migration,accounting for 87%–89%of the total accumulation.The strong hygroscopicity and high Pb activity of PM1 emitted from waste incineration(WI)increased the Pb absorption coefficient via the hydrophilic and liquid film migration pathway.In contrast,the high hydrophobicity of PM1 from coal burning(CB)led to greater retention of Pb on leaf surfaces.Both foliar reactive oxygen metabolism and photosynthesis indices were sensitive to air pollution.Foliar metal(loid)accumulation and airborne PM1 concentration accounted for the variance in physiological responses in rice leaves.Our results also indicated that Pb was the key element in PM1 emissions from both coal burning(CB)and waste incineration(WI)responsible for significant physiological changes in rice leaves. 展开更多
关键词 Metal(loid) PM1 exposure Coal burning Waste incineration Physiological response Particle nature
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Spray-dried MOF-derived bimetallic oxide/carbon hybrids with superior electron transfer capability for catalyzing ammonium perchlorate decomposition
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作者 Tianjin Zhi Dongze Li +3 位作者 Yan Li Zhenxin Yi Shunguan Zhu Lin Zhang 《Defence Technology(防务技术)》 2026年第1期224-240,共17页
The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performa... The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performance improvement of kinds of catalysts.In this study,bimetallic metal-organic frameworks(MOFs),such as CuCo-BTC(BTC=1,3,5-Benzenetricarboxylic acid,H_(3)BTC),CuNi-BTC,and CoNi-BTC,were synthesized by solvothermal(ST)and spray-drying(SD)methods,and then calcined at 400℃for 2 h to form metal oxides.The catalysts as well as their catalytic effects for AP decomposition were characterized by FTIR,XRD,SEM,XPS,TG,DSC,TG-IR,EIS,CV,and LSV.It was found that the rapid coordination of metal ions with ligands during spray drying may lead to catalytic structural defects,promoting the exposure of reactive active sites and increasing the catalytic active region.The results showed that the addition of 2 wt%binary transition metal oxides(BTMOs)as catalysts significantly reduced the high-temperature decomposition(HTD)temperature of AP and enhanced its heat release.Of particular significance is the observation that SD-CoNiO_(x),prepared by spray-drying,reduced the decomposition temperature of AP from 413.26℃(pure AP)to 306℃and enhanced the heat release from 256.79 J/g(pure AP)to 1496.82 J/g,while concomitantly reducing the activation energy by 42%.By analysing the gaseous products during the decomposition of AP+SD-CoNiO_(x)and AP+ST-CoNiO_(x),it was found that SD-CoNiO_(x)could significantly increase the content of high-valent nitrogen oxides during the AP decomposition reaction,which indicates that the BTMOs prepared by spray-drying in the reaction system are more conducive to accelerating the electron transfer in the thermal decomposition process of AP,and can provide a high concentration of reactive oxygen species that oxidize AP to high-valent nitrogen oxide-containing compounds.The present study shows that the structure selectivity of the spray-drying technique influences surfactant molecular arrangement on catalyst surfaces,resulting in their ability to promote higher electron transfer during the catalytic process.Therefore,BTMOs prepared by spray drying method have higher potential for application. 展开更多
关键词 Metal-organic framework derivatives Combustion catalyst Binary transition metal oxides Ammonium perchlorate
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Atomic-level local-structure engineering of Pt-group oxygen electrocatalysts for fuel cells and water electrolyzers
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作者 Yang Ji Haixia Zhong +5 位作者 Liang Qiao Caini Ma Qinyi Hu Yuri Nikolaichik Kebin Chi Xinbo Zhang 《Nano Research》 2026年第1期159-179,共21页
Proton-exchange membrane fuel cell and water electrolyzer(PEMFC and PEMWE)with high conversion efficiency and zero-carbon emission stand out as an attractive strategy for efficient conversion between hydrogen energy a... Proton-exchange membrane fuel cell and water electrolyzer(PEMFC and PEMWE)with high conversion efficiency and zero-carbon emission stand out as an attractive strategy for efficient conversion between hydrogen energy and renewable electricity.As a key component,efficient oxygen electrocatalyst for promoting sluggish reaction kinetics of oxygen reduction and evolution reaction(ORR and OER)under harsh operation conditions severely limited progress of these devices.Among various candidates,Ptgroup(Pt,Ir,and Ru)-based electrocatalysts are still the most active ORR/OER catalysts.However,the scarcity,high cost,and questionable stability restrict the widespread applications and the commercialization of PEMWE/PEMFC.Progresses in synthesizing atomically dispersed single/multiple-atom catalysts(SACs/MACs)offer new opportunities to Pt-group ORR/OER catalysts owing to nearly 100% metal utilization and high catalytic activities.Extensive efforts have been continuously devoted to optimizing the local structure of Pt-group OER/ORR catalysts at atom-level for further enhancing stability and activity.In this review,universal synthesis methods to prepare Ptgroup SACs are discussed first,highlighting crucial factors which affect the structure and catalytic performance.Afterward,advanced characterization techniques for directly confirming atomic dispersed metal atoms were introduced,including aberration-corrected high-angle-annular-dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy.Importantly,considerations for rational catalyst design and typical Pt-group SACs/MACs are summarized regarding the regulation strategy of atomically dispersed metal sites and various supports,and effects of metal-support interaction on the catalytic performance.Finally,key challenges and proposed perspectives for future development of atomically dispersed Pt-group oxygen electrocatalysts for fuel cell and electrolyzer are briefly discussed. 展开更多
关键词 Pt-group metal single-atom electrocatalyst oxygen reduction reaction oxygen evolution reaction fuel cell water electrolyzer
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In‑Operando X‑Ray Imaging for Sobering Examination of Aqueous Zinc Metal Batteries
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作者 Yuhang Dai Hongzhen He +4 位作者 Mengzheng Ouyang Jianuo Chen Jie Lin Haobo Dong Guanjie He 《Nano-Micro Letters》 2026年第3期330-337,共8页
Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing car... Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing carefully designed cells that approximate the structural characteristics of practical batteries,we revisit this widely held view through in-operando X-ray radiography to examine zinc dendrite formation and HER under nearpractical operating conditions.While conventional understanding emphasizes the severity of these processes,our findings suggest that zinc dendrites and HER are noticeably less pronounced in dense,real-operation configurations compared to modified cells,possibly due to a more uniform electric field and the suppression of triple-phase boundaries.This study indicates that other components,such as degradation at the cathode current collector interface and configuration mismatches within the full cell,may also represent important barriers to the practical application of AZMBs,particularly during the early stages of electrodeposition. 展开更多
关键词 Aqueous Zn metal batteries X-ray imaging In situ characterization Degradation mechanism
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Boosting Li^(+) transport in ultra-stable all-solid-state lithium metal batteries via bimetal oxide enhanced PrBaCoFeO_(5+δ) perovskite nanofillers
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作者 Jiamin Li Shuyu Bi +5 位作者 Tong Duan Yanbo Liu Qiangchao Sun Tao Hu Xionggang Lu Hongwei Cheng 《Nano Research》 2026年第1期563-575,共13页
Composite solid-state electrolytes(CSEs)have garnered significant attention for nextgeneration energy storage owing to their inherent safety features compared with those of their liquid counterparts.However,their prac... Composite solid-state electrolytes(CSEs)have garnered significant attention for nextgeneration energy storage owing to their inherent safety features compared with those of their liquid counterparts.However,their practical deployment remains hindered by sluggish lithium-ion transport kinetics and interfacial instability.Herein,we introduced a bimetal oxide enhanced strategy for oxygen-vacancy-engineered double perovskite nanofillers(PrBaCoFeO_(5+δ)(PBCF))to address these challenges in polyethylene oxide(PEO)-based CSEs.The strong Lewis acid-base coordination between Co^(3+)/Fe^(3+)sites on PBCF and ether oxygen groups in PEO effectively suppresses the polymer-chain crystallization while creating continuous Li^(+)conduction pathways.Importantly,the abundant oxygen vacancies serve as catalytic centers to decompose lithium bis(trifluoromethanesulfonyl)imide(LiTFSI),thereby forming a robust organic-inorganic hybrid solid electrolyte interphase(SEI).Consequently,the prepared PEO-LiTFSI-PBCF CSE achieves an improved Li^(+)ionic conductivity of 2.76×10^(-4) S·cm^(-1)(30℃)and an elevated Li^(+)transference number(0.54).The Li||Li symmetric cell exhibits impressive lithium plating/stripping ability(>6000 h at 0.1 mA·cm^(-2))and practical viability in Li||LiFePO_(4)full cells with 90.1% capacity retention after 500 cycles at 30℃(0.3 C).This defect engineering strategy provides new insights into the construction of fast and stable Li^(+)transport channels in polymer solid-state electrolytes,paving the way for high-energy-density all-solid-state lithium metal batteries. 展开更多
关键词 composite solid electrolytes double-perovskite filler Lewis acid-base interaction interfacial catalysis allsolid-state lithium metal batteries
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Metal nanoclusters engineered interfacial adsorption for enhanced ROS independent oxidase-mimicking activity
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作者 Min Qi Yutong Ye +8 位作者 Yuling Xu Qian Lei Fengxian Zhang Zhi Chen Jiaji Cheng Cao Li Yijing Liu Yi Liu Ziqiang Xu 《Nano Research》 2026年第1期409-417,共9页
Recently,reactive oxygen species(ROS)-independent mimetics of oxidase with Au nanoclusters(NCs)as the catalysts and MnO_(2)as electron acceptor have gained attention.In this study,we aim to explore the oxidase-mimicki... Recently,reactive oxygen species(ROS)-independent mimetics of oxidase with Au nanoclusters(NCs)as the catalysts and MnO_(2)as electron acceptor have gained attention.In this study,we aim to explore the oxidase-mimicking potential of bovine serum albumin(BSA)-templated metal nanoclusters(BSA-M NCs,where M=Ag,Pt,Cu,or Cd)beyond Au NCs in boosting the oxidation of 3,3',5,5'-tetramethylbenzidine(TMB)by MnO_(2),denoted as BM@Metal.The oxidase-mimetic activity of BM@Metal is independent of ROS and generally enhanced by the incorporation of metal nanoclusters.Notably,this enhancement varies with the metal species,with BSA-Cd exhibiting the highest activity.The X-ray photoelectron spectroscopy(XPS)analysis confirms mixed valence states(Mn(Ⅳ)/Mn(Ⅱ))in BM@Cd.Given that the catalytic activity is closely linked to the substrate adsorption,the label-free isothermal titration calorimetry was employed to probe the affinity between TMB and BSA-M NCs,which provides a robust approach for probing the interface adsorption.The results reveal that the superior catalytic performance of BSA-Cd correlates with enhanced TMB adsorption,likely facilitated by coordination and hydrophobic interactions.Finally,the superior catalytic performance of BSA-M NCs on the oxidation of TMB by MnO_(2)has inspired us to fabricate the assay for analyzing α-glucosidase’s activity.This work not only demonstrates the versatility of metal NCs in constructing ROS-independent oxidase mimetics but also provides interfacial adsorption engineered strategy for the rational design of superior ROS independent mimetics of natural oxidase. 展开更多
关键词 reactive oxygen species(ROS)-independent oxidase-like interface adsorption manganese oxide metal nanoclusters
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Achieving dark current suppression and photocurrent enhancement simultaneously in 2D MoS_(2) photodetector via Ag_(70) nanocluster modification
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作者 Xiao-Zong Hu Jing Li +3 位作者 Huai-Zhen Ji Qian-Fang Ren Xi-Ming Luo Shuang-Quan Zang 《Nano Research》 2026年第1期1102-1110,共9页
Two-dimensional(2D)MoS_(2) is considered an excellent candidate material for nextgeneration photodetectors.However,the high dark current and low photocurrent in MoS_(2) devices severely hinder their practical applicat... Two-dimensional(2D)MoS_(2) is considered an excellent candidate material for nextgeneration photodetectors.However,the high dark current and low photocurrent in MoS_(2) devices severely hinder their practical application.Strategies for suppressing dark current and enhancing photocurrent should be explored.Herein,we propose a modification strategy for MoS_(2) by utilizing Ag_(70) nanoclusters(NCs)as electron reservoirs and photoabsorbers to suppress dark current and enhance the photocurrent of 2D MoS_(2) photodetector.Remarkably,the dark current is effectively suppressed by four orders of magnitude,while the photocurrent is enhanced by over tenfold upon modification with Ag_(70) NCs,compared to the pristine MoS_(2) photodetector.The reduction in dark current is attributed to charge transfer from MoS_(2) to Ag_(70) NCs owing to the strong electronwithdrawing property of Ag_(70) NCs.The increase in photocurrent benefits from enhanced optical absorption of the photodetector after Ag_(70) NCs modification and the subsequent injection of photoexcited electrons from Ag_(70) NCs to MoS_(2).Compared to isolated MoS_(2),the modulated photodetector shows exceptional improvements in several key figures of merit(such as responsivity,detectivity,external quantum efficiency,and photoswitching on/off ratio).This study opens up new avenues for building high-performance 2D MoS_(2) photodetectors. 展开更多
关键词 metal nanocluster MoS_(2)photodetector dark current suppression photocurrent enhancement
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