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Cooling rate dependence of polymorph selection during rapid solidification of liquid metal zinc 被引量:4
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作者 田泽安 周丽丽 +2 位作者 莫云飞 梁永超 刘让苏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4072-4079,共8页
The polymorph selection during rapid solidification of zinc melt was investigated by molecular dynamics simulation. Several methods including g(r), energy, CNS, basic cluster and visualization were used to analyze t... The polymorph selection during rapid solidification of zinc melt was investigated by molecular dynamics simulation. Several methods including g(r), energy, CNS, basic cluster and visualization were used to analyze the results. The results reveal that the cooling rate has no observable effect on the microstructure as TTc(Tc is the onset temperature of crystallization); and at the first stage of crystallization, although microstructures are different, the morphologies of nucleus are similar, which are composed of HCP and FCC layers; the polymorph selection of cooling rate finally takes place at the second stage of crystallization: at a high cooling rate, the rapid increase of FCC atoms leads to a FCC crystal mixed with less HCP structures; while at a low cooling rate, HCP atoms grow at the expense of FCC atoms, resulting in an almost perfect HCP phase. The results reveal that the cooling rate is one of the important factors for polymorph selection. 展开更多
关键词 polymorph selection crystal structure rapid solidification metal zinc molecular dynamics simulation
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Preparation of metal zinc from hemimorphite by vacuum carbothermic reduction with CaF_2 as catalyst 被引量:3
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作者 熊利芝 陈启元 +3 位作者 尹周澜 张平民 丁治英 刘志雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期694-699,共6页
Zn reduction was investigated by the vacuum carbothermic reduction of hemimorphite with or without CaF2 as catalyst.Results indicate that CaF2 can catalyze the carbothermic reduction of zinc silicate,decrease the reac... Zn reduction was investigated by the vacuum carbothermic reduction of hemimorphite with or without CaF2 as catalyst.Results indicate that CaF2 can catalyze the carbothermic reduction of zinc silicate,decrease the reaction temperature and time.The lower the reaction temperature and the more the amount of CaF2,the better the catalytic effect.The optimal process condition is obtained as follows:the addition of about 10% CaF2,the reaction temperature of 1373 K,the molar ratio of C to ZnTotal of 2.5,the pressure of system lower than 20 kPa,the reaction time of about 40 min.Under the optimal process condition,the zinc reduction rate is about 93% from hemimorphite. 展开更多
关键词 metal zinc calcium fluoride CATALYSIS carbothermic reduction HEMIMORPHITE
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Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries 被引量:1
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作者 Changchun Fan Weijia Meng Jiaye Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期79-110,I0003,共33页
Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon neutrality.Due to the discontinuous and inco nsistent nature of common clean energy sources,hi... Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon neutrality.Due to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this target.Aqueous zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy storage.However,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of AZMBs.An increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of AZMBs.This review aims to provide a comprehensive overview of the fundamentals and challenges of AZMBs.Resea rch strategies for interfacial modification of ZMAs are systematically presented.The features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery performance.Finally,perspectives are provided on the problems and challenges of ZMAs.This review is expected to offer a constructive reference for the further development and commercialization of AZMBs. 展开更多
关键词 Aqueous zinc metal batteries zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating
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Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures 被引量:1
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作者 Xianfu Zhang Long Zhang +2 位作者 Xinyuan Jia Wen Song Yongchang Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期305-349,共45页
Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low re... Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented. 展开更多
关键词 Aqueous zinc metal batteries zinc anodes High zinc utilization Depth of discharge Anode-free structures
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Stable and reversible zinc metal anode with fluorinated graphite nanosheets surface coating
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作者 Hong CHANG Zhen-ya LUO +2 位作者 Xue-ru SHI Xin-xin CAO Shu-quan LIANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3358-3371,共14页
A highly stable zinc metal anode modified with a fluorinated graphite nanosheets(FGNSs)coating was designed.The porous structure of the coating layer effectively hinders lateral mass transfer of Zn ions and suppresses... A highly stable zinc metal anode modified with a fluorinated graphite nanosheets(FGNSs)coating was designed.The porous structure of the coating layer effectively hinders lateral mass transfer of Zn ions and suppresses dendrite growth.Moreover,the high electronegativity exhibited by fluorine atoms creates an almost superhydrophobic solid-liquid interface,thereby reducing the interaction between solvent water and the zinc substrate.Consequently,this leads to a significant inhibition of hydrogen evolution corrosion and other side reactions.The modified anode demonstrates exceptional cycling stability,as symmetric cells exhibit sustained cycling for over 1400 h at a current density of 5 mA/cm^(2).Moreover,the full cells with NH_(4)V_(4)O_(10)cathode exhibit an impressive capacity retention rate of 92.2%after undergoing 1000 cycles. 展开更多
关键词 fluorinated graphite hydrophobic coating ANTI-CORROSION dendrite suppression zinc metal anode
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Achieving an ion-homogenizing and corrosion-resisting interface through nitro-coordination chemistry for stable zinc metal anodes
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作者 Jizhen Wang Long Jiao +14 位作者 Qiaoyun Liu Wei Xin Yechen Lei Tian Zhang Leixin Yang Dengkun Shu Shuo Yang Kaihua Li Chenyang Li Chao Yi Hongyuan Bai Yuchao Ma Huan Li Wenjun Zhang Bowen'Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期10-18,共9页
Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-me... Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-metal batteries.To address these challenges,we report in this study a functional nitro-cellulose interfacial layer(NCIL)on the surface of Zn anodes enlightened by a nitro-coordination chemistry strategy.The NCIL exhibits strong zincophilicity and superior coordination capability with Zn^(2+)due to the highly electronegative and highly nucleophilic nature of the nitro functional group.This characteristic facilitates a rapid Zn-ion desolvation process and homogeneous Zn plating,effectively preventing H_(2) evolution and dendrite formation.Additionally,the negatively charged surface of NCIL acts as a shield,repelling SO_(4)^(2-)anions and inhibiting corrosive reactions on the Zn surface.Remarkably,reversible and stable Zn plating/stripping is achieved for over 5100 h at a current density of 1 mA cm^(-2),which is nearly 30 times longer than that of bare Zn anodes.Furthermore,the Zn/V_(2)O_(5) full cells with the functional interface layer deliver a high-capacity retention of 80.3%for over 10,000 cycles at 5 A g^(-1).This research offers valuable insights for the rational development of advanced protective interface layers in order to achieve ultra-long-lifeZnmetal batteries. 展开更多
关键词 zinc metal anode Nitro-cellulose interfacial layer Coordination capability Dendrite-free deposition Long-term cycling
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Imide-pillared covalent organic framework protective films as stable zinc ion-conducting interphases for dendrite-free Zn metal anodes
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作者 Xiaoman Ye Xuemei Xiao +3 位作者 Zhijing Wu Xin Wu Lin Gu Sheng Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期470-477,I0010,共9页
The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared cov... The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for ZMAs.Compared to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn dendrites.Impressively,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 cycles.The present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs. 展开更多
关键词 Aqueous zinc ion batteries zinc metal anodes Surface modification Covalent organic frameworks Imide linkage
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Rational screening of metal coating on Zn anode for ultrahigh-cumulative-capacity aqueous zinc metal batteries 被引量:2
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作者 Dan Lv Huili Peng +4 位作者 Cheng Wang Hongxia Liu Dongdong Wang Jian Yang Yitai Qian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期81-88,共8页
Aqueous zinc metal batteries feature intrinsic safety,but suffer from severe dendrite growth and water-derived side reactions.Many metal coatings have been explored for stabilizing Zn metal anode via a trialand-error ... Aqueous zinc metal batteries feature intrinsic safety,but suffer from severe dendrite growth and water-derived side reactions.Many metal coatings have been explored for stabilizing Zn metal anode via a trialand-error approach.Here,we propose an exercisable way to screen the potential metal coating on Zn anodes in view of de-polarization effect and dendrite-suppressing ability theoretically.As an output of this screening,cadmium(Cd) metal is checked experimentally.Therefore,symmetric ZnllZn cells using Cd coated Zn(Zn@Cd) exhibit an ultra-long cycle life of 3500 h(nearly 5 months) at a high current density of 10 mA cm^(-2),achieving a record-high cumulative capacity(35 A h cm^(-2)) compared to the previous reports.The full cells of Zn@Cd‖MnO_(2) display a markedly improved cycling performance under harsh conditions including a limited Zn supply(N/P ratio=1.7) and a high areal capacity(3.5 mA h cm^(-2)).The significance of this work lies in not only the first report of Cd coating for stabilizing Zn metal anode,but also a feasible way to screen the promising metal materials for other metal anodes. 展开更多
关键词 zinc metal batteries Cadmium coating Redox potentials Surface energy Cumulative capacity
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Manipulating the ion-transference and deposition kinetics by regulating the surface chemistry of zinc metal anodes for rechargeable zinc-air batteries
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作者 Miao He Chaozhu Shu +8 位作者 Ruixing Zheng Wei Xiang Anjun Hu Yu Yan Zhiqun Ran Minglu Li Xiaojuan Wen Ting Zeng Jianping Long 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期318-330,共13页
Aqueous zinc-air battery(ZAB)has attractive features as the potential energy storage system such as high safety,low cost and good environmental compatibility.However,the issue of dendrite growth on zinc metal anodes h... Aqueous zinc-air battery(ZAB)has attractive features as the potential energy storage system such as high safety,low cost and good environmental compatibility.However,the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB.Herein,the N-doped carbon cloth(NC)prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth.Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn^(2+)by boosting the desolvation process of Zn^(2+),eventually reducing the nucleation overpotential.Besides,theoretical calculation results confirm the zincophilicity of N-containing functional group(such as pyridine N and pyrrole N),which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn^(2+) in the vicinity of the surface and enhancing its interaction with zinc atoms.As a result,the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8%and long-term stability of over 500 cycles at 0.2 mA cm^(-2).And the Coulombic efficiency reached about 99.5%at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm^(-2).The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV.In addition,the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh g_(Zn)^(-1) and a long life of over 430 cycles.The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn^(2+) presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes. 展开更多
关键词 zinc metal anodes Dendrite-free Surface chemical regulation Ion-transference kinetics Aqueous zinc-air battery
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Recent Progress and Prospects on Dendrite-free Engineerings for Aqueous Zinc Metal Anodes
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作者 Jiangmin Jiang Zhiwei Li +5 位作者 Zhenghui Pan Shijing Wang Yaxin Chen Quanchao Zhuang Zhicheng Ju Xiaogang Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期286-302,共17页
Rechargeable zinc-ion batteries with mild aqueous electrolytes are one of the most promising systems for large-scale energy storage as a result of their inherent safety,low cost,environmental-friendliness,and acceptab... Rechargeable zinc-ion batteries with mild aqueous electrolytes are one of the most promising systems for large-scale energy storage as a result of their inherent safety,low cost,environmental-friendliness,and acceptable energy density.However,zinc metal anodes always suffer from unwanted dendrite growth,leading to low Coulombic efficiency and poor cycle stability and during the repeated plating/stripping processes,which substantially restrict their further development and application.To solve these critical issues,a lot of research works have been dedicated to overcoming the drawbacks associated with zinc metal anodes.In this overview,the working mechanisms and existing issues of the zinc metal anodes are first briefly outlined.Moreover,we look into the ongoing processes of the different strategies for achieving highly stable and dendrite-free zinc metal anodes,including crystal engineering,structural engineering,coating engineering,electrolyte engineering,and separator engineering.Finally,some challenges being faced and prospects in this field are provided,together with guiding significant research directions in the future. 展开更多
关键词 dendrite-free engineerings interfacial electrochemistry mild aqueous electrolyte zinc metal anodes zinc-ion batteries
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Apoptosis of Spodoptera litura larval hemocytes induced byheavy metal zinc 被引量:9
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作者 XIA Qiang SUN Hongxia HU Xinjun SHU Yinghua GU Dexiang ZHANG Guren 《Chinese Science Bulletin》 SCIE EI CAS 2005年第24期2856-2860,共5页
By adding different amount of zinc into the artificial medium of the insect larvae, the zinc-induced apoptosis of the larvae haemocytes of the herbivorous insect Spodoptera litura Fabricius was investigated with flow ... By adding different amount of zinc into the artificial medium of the insect larvae, the zinc-induced apoptosis of the larvae haemocytes of the herbivorous insect Spodoptera litura Fabricius was investigated with flow cy- tometer. The results showed that the increase of zinc dose in the artificial feed led to the accumulations of zinc in the lar- val hemolymph and fat body, and more zinc was accumu- lated in fat body than in hemolymph. The apoptosis of hemocytes was significantly induced at high zinc concentra- tion (1000 mg·kg?1) in the insect diet, and the apoptosis rate was 63.63%, which was remarkably higher than that at con- trol and lower concentrations (50―500 mg·kg?1). This sug- gests that the high dose of zinc in the artificial diet of S. litura larvae could induce the apoptosis of the larval hemocytes of S. litura. 展开更多
关键词 重金属污染 草地夜蛾 幼虫 血细胞 细胞凋亡
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Different surface modification methods and coating materials of zinc metal anode 被引量:9
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作者 Feng Tao Yong Liu +6 位作者 Xinyuan Ren Jing Wang Yazhou Zhou Yingjie Miao Fengzhang Ren Shizhong Wei Jianmin Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期397-412,I0011,共17页
Rechargeable aqueous Zn-ion batteries(AZIBs)are one of the most promising energy storage devices for large-scale energy storage owing to their high specific capacity,eco-friendliness,low cost and high safety.Neverthel... Rechargeable aqueous Zn-ion batteries(AZIBs)are one of the most promising energy storage devices for large-scale energy storage owing to their high specific capacity,eco-friendliness,low cost and high safety.Nevertheless,zinc metal anodes suffer from severe dendrite growth and side reactions,resulting in the inferior electrochemical performance of AZIBs.To address these problems,surface modification of zinc metal anodes is a facile and effective method to regulate the interaction between the zinc anode and an electrolyte.In this review,the current challenges and strategies for zinc metal anodes are presented.Furthermore,recent advances in surface modification strategies to improve their electrochemical performance are concluded and discussed.Finally,challenges and prospects for future development of zinc metal anodes are proposed.We hope this review will be useful for designing and fabricating highperformance AZIBs and boosting their practical applications. 展开更多
关键词 Zn-ion batteries zinc metal anode Surface modification Solvent casting method Wet chemistry method
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Issues and Future Perspective on Zinc Metal Anode for Rechargeable Aqueous Zinc-ion Batteries 被引量:36
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作者 Canpeng Li Xuesong Xie +1 位作者 Shuquan Liang Jiang Zhou 《Energy & Environmental Materials》 2020年第2期146-159,共14页
Rechargeable aqueous zinc-ion batteries(ZIBs) featuring the merits of low cost,eco-friendliness,and enhanced safety have attracted extensive interests and considered as the most promising energy storage system.However... Rechargeable aqueous zinc-ion batteries(ZIBs) featuring the merits of low cost,eco-friendliness,and enhanced safety have attracted extensive interests and considered as the most promising energy storage system.However,much efforts are devoted to the exploration of cathode materials and their storage mechanisms in this system,and inadequate attentions are received in regard to anode side especially in neutral or mild acidic electrolyte.Therefore,in this review,the fundamental understanding of existing issues including dendrite formation,corrosion,and hydrogen evolution are mainly revealed,as well as their interaction in neutral or mild acidic medium.In addition,the currently existing solution strategies on the anode are summarized and the mechanisms that contained are simultaneously investigated.Finally,perspectives on future anode modification and innovation direction are provided for the further development and research of Zn-based ZIBs. 展开更多
关键词 dendrite formation hydrogen evolution zinc corrosion zinc metal anode zinc-ion batteries
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Mineralogy, geochemistry and release of heavy metals in wastes from indigenous zinc smelting in Northwest Guizhou 被引量:1
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作者 Pan WU Congqiang LIU +1 位作者 Yuangen YANG Guoping ZHANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期42-42,共1页
关键词 矿山环境 环境地质化学 重金属 锌矿 熔炼废物
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Critical factors to inhibit water-splitting side reaction in carbon-based electrode materials for zinc metal anodes 被引量:1
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作者 Dong Hyuk Kang Eunji Lee +11 位作者 Beom Sik Youn Son Ha Jong Chan Hyun Juhee Yoon Dawon Jang Kyoung Sun Kim Hyungsub Kim Sang Moon Lee Sungho Lee Hyoung-Joon Jin Hyung-Kyu Lim Young Soo Yun 《Carbon Energy》 SCIE CAS 2022年第6期1080-1092,共13页
Zinc metal anodes(ZMA)have high theoretical capacities(820 mAh g−1 and 5855 mAh cm−3)and redox potential(−0.76 V vs.standard hydrogen electrode),similar to the electrochemical voltage window of the hydrogen evolution ... Zinc metal anodes(ZMA)have high theoretical capacities(820 mAh g−1 and 5855 mAh cm−3)and redox potential(−0.76 V vs.standard hydrogen electrode),similar to the electrochemical voltage window of the hydrogen evolution reaction(HER)in a mild acidic electrolyte system,facilitating aqueous zinc batteries competitive in next-generation energy storage devices.However,the HER and byproduct formation effectuated by water-splitting deteriorate the electrochemical performance of ZMA,limiting their application.In this study,a key factor in promoting the HER in carbon-based electrode materials(CEMs),which can provide a larger active surface area and guide uniform zinc metal deposition,was investigated using a series of threedimensional structured templating carbon electrodes(3D-TCEs)with different local graphitic orderings,pore structures,and surface properties.The ultramicropores of CEMs are the determining critical factors in initiating HER and clogging active surfaces by Zn(OH)2 byproduct formation,through a systematic comparative study based on the 3D-TCE series samples.When the 3D-TCEs had a proper graphitic structure with few ultramicropores,they showed highly stable cycling performances over 2000 cycles with average Coulombic efficiencies of≥99%.These results suggest that a well-designed CEM can lead to high-performance ZMA in aqueous zinc batteries. 展开更多
关键词 aqueous batteries carbon electrode hydrogen evolution reaction multivalent ion zinc metal anode
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Kinetic Study of Cementation of Copper on Zinc Metal in Ethanol-Water Mixtures 被引量:1
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作者 A.A.Zaghloul G.M.EI-Subruiti and A.M.Ahmed(Chemistry Depatment, Faculty of Science, Alexandria University Alexandria, Egypt) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第1期41-45,共5页
The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. Moreover,the rates of this reaction ... The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. Moreover,the rates of this reaction at 0.15 mol'L-1 copper sulphate solution have been measured in a varietyof ethanol-water media at temperatures from 20℃ to 40℃. The correlation between the masstransfer coefficient and the dielectric constant has been investigated. Also, the thermodynamicparameters of activation have been calculated. The isokinetic relationship reveals the existenceof compensation effect, where the solute-solvent interactions play an important role. 展开更多
关键词 FIGURE Kinetic Study of Cementation of Copper on zinc metal in Ethanol-Water Mixtures
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Heavy metal concentrations in soils and plants in the vicinity of Arufu lead-zinc mine, Middle Benue Trough, Nigeria 被引量:3
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作者 Nganje T.N. Adamu C.I. Ukpong E.E. 《Chinese Journal Of Geochemistry》 EI CAS 2010年第2期167-174,共8页
This study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from c... This study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). The samples were analyzed for heavy metals (Fe, Zn, Mn, Cu, Pb, Cr and Cd) by Atomic Absorption Spectrophotometry (AAS). The physical properties of soils (pH and LOI) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (<10%). Levels of Zn, Pb and Cd in culti-vated soils were higher than the concentrations obtained from the control site. These heavy metals are most probably sourced from mining and agricultural activities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leaves>cassava tubers>peelings. In the same plant species, metal levels decreased in the order of Zn>Fe>Mn>Cu>Pb>Cr>Cd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and Cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOI as some of the factors influencing soil-plant metal uptake. 展开更多
关键词 土壤重金属含量 土壤样品 植物样本 铅锌矿 尼日利亚 原子吸收光谱法 线性回归分析 amp
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Ecological risk assessment of heavy metals in surface seawater and sediment near the outlet of a zinc factory in Huludao City, Liaoning Province, China 被引量:3
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作者 冯永亮 陈燕珍 +4 位作者 王静 宫玉峰 刘希刚 牟刚 田华 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第6期1320-1331,共12页
At present, the methods widely applied to assess ecological risk of heavy metals are essentially single-point estimates in which exposure and toxicity data cannot be fully used and probabilities of adverse biological ... At present, the methods widely applied to assess ecological risk of heavy metals are essentially single-point estimates in which exposure and toxicity data cannot be fully used and probabilities of adverse biological effects cannot be achieved. In this study, based on investigation of concentrations of six heavy metals(As, Hg, Pb, Cd, Cu, and Zn) in the surface seawater and sediment near the outlet of a zinc factory, located in Huludao City, Liaoning Province, China, a tiered approach consisting of several probabilistic options was used to refi ne ecological risk assessment for the individuals. A mixture of various heavy metals was detected in the surface seawater, and potential ecological risk index(PERI) was adopted to assess the potential ecological risk of heavy metals in the surface sediment. The results from all levels of aquatic ecological risk assessment in the tiered framework, ranging from comparison of single effects and exposure values to the use of distribution-based Hazard Quotient obtained through Monte Carlo simulation, are consistent with each other. Briefl y, aquatic Zn and Cu posed a clear ecological risk, while Cd, Pb, Hg, and As in the water column posed potential risk. As expected, combined ecological risk of heavy metal mixture in the surface seawater was proved signifi cantly higher than the risk caused by any individual heavy metal, calculated using the concept of total equivalent concentration. According to PERI, the severity of pollution by the six heavy metals in the surface sediment decreased in the following sequence: Cd>Hg>As>Pb>Cu>Zn, and the total heavy metals in the sediment posed a very high risk to the marine environment. This study provides a useful mathematical framework for ecological risk assessment of heavy metals. 展开更多
关键词 heavy metal ecological risk assessment zinc factory joint probability curve Monte Carlo potential ecological risk index
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Alkaline leaching of metal melting industry wastes and separation of zinc and lead in the leach solution 被引量:2
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作者 Lin, M. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第4期452-457,共6页
In this work, a thorough examinations on the extractability of zinc and lead present in the steelmaking dusts using alkaline leaching process and the effectiveness of the zinc and lead separation in the resultant leac... In this work, a thorough examinations on the extractability of zinc and lead present in the steelmaking dusts using alkaline leaching process and the effectiveness of the zinc and lead separation in the resultant leaching solutions using sulfide precipitation method were made. It was found that only about 53% of zinc and over 70% of the lead could be leached out of the dusts, while the other 47% of zinc and 30% of lead were left in the leaching residues. The zinc and lead in the resultant leaching solution can be effectively and selectively separated. When the weight ratio of sodium sulfide (M.W. = 222-240) to Pb was kept at 1.8, the lead in the solution could be precipitated out quantitatively while all the zinc was remained in the solution. The zinc left in the solution can be further recovered by the addition of extra sodium sulfide with a weight ratio of sodium sulfide to the zinc over 2.6. The resultant filtrate can be recycled to the leaching of dust in the next leaching process. 展开更多
关键词 Alkaline earth metals DUST Industrial wastes LEAD metal melting Sodium compounds zinc
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Ultrasonic-enhanced Stereoselective Debromination of vic-Dibromides to Alkenes with Metallic Zinc Powder in Aqueous Media
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作者 LIPin-hua RAOWan-ping +1 位作者 WANGMin WANGLei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期598-601,共4页
Carbon-carbon double bond functional groups are often protected through a popular bromination/debromination method because of their reactivity. An ultrasonic-enhanced stereoselective debromination of vic-dibromides wi... Carbon-carbon double bond functional groups are often protected through a popular bromination/debromination method because of their reactivity. An ultrasonic-enhanced stereoselective debromination of vic-dibromides with metallic zinc powder in aqueous media has been developed, which generates E-alkenes with excellent yields. The reactivity of vic-dibromides decreases in the order of 1,2-dibromo-1,2-diphenylethane>1,2-dibromo-1-phenylethane>1,2-dibromo-1,2-dialkylethane. 展开更多
关键词 Stereoselective debromination vic-Dibromides ALKENES metallic zinc Ultrasonic irradiation Aqueous medium
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