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Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage
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作者 Peng Gao Pei Tang +7 位作者 Ying Mo Peitao Xiao Wang Zhou Shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期909-918,共10页
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ... Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties. 展开更多
关键词 manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching Selective bond breakage Surface reconstruction Charge storage mechanisms
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Integration of morphology and electronic structure modulation on cobalt phosphide nanosheets to boost photocatalytic hydrogen evolution from ammonia borane hydrolysis 被引量:2
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作者 Chao Wan Yu Liang +5 位作者 Liu Zhou Jindou Huang Jiapei Wang Fengqiu Chen Xiaoli Zhan Dang-guo Cheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期333-343,共11页
The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy.Ammonia borane(AB)has regarded as a competitive candidate for ... The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy.Ammonia borane(AB)has regarded as a competitive candidate for chemical hydrogen storage.However,developing efficient yet high-performance catalysts towards hydrogen evolution from AB hydrolysis remains an enormous challenge.Herein,cobalt phosphide nanosheets are synthesized by a facile salt-assisted along with low-temperature phosphidation strategy for simultaneously modulating its morphology and electronic structure,and function as hydrogen evolution photocatalysts.Impressively,the Co_(2)P nanosheets display extraordinary performance with a record high turnover frequency of 44.9 min^(-1),outperforming most of the noble-metal-free catalysts reported to date.This remarkable performance is attributed to its desired nanosheets structure,featuring with high specific surface area,abundant exposed active sites,and short charge diffusion paths.Our findings provide a novel strategy for regulating metal phosphides with desired phase structure and morphology for energy-related applications and beyond. 展开更多
关键词 Ammonia borane Hydrogen generation HYDROLYSIS cobalt phosphide nanosheets PHOTOCATALYSIS
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Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation 被引量:1
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作者 Yuhua Qiu Yingping Huang +2 位作者 Yanlan Wang Xiang Liu Di Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2770-2780,共11页
Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive speci... Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive species,including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radical(·O_(2)^(-)),and singlet oxygen(1O_(2)),which can induce the degradation of organic contaminants.In this work,we synthesized a variety of M-OMS-2 nanorods(M=Co,Ni,Cu,Fe)by doping Co^(2+),Ni^(2+),Cu^(2+),or Fe^(3+)into manganese oxide oc-tahedral molecular sieve(OMS-2)to efficiently remove sulfamethoxazole(SMX)via PMS activation.The catalytic performance of M-OMS-2 in SMX elimination via PMS activation was assessed.The nanorods obtained in decreasing order of SMX removal rate were Cu-OMS-2(96.40%),Co-OMS-2(88.00%),Ni-OMS-2(87.20%),Fe-OMS-2(35.00%),and OMS-2(33.50%).Then,the kinetics and struc-ture-activity relationship of the M-OMS-2 nanorods during the elimination of SMX were investigated.The feasible mechanism underly-ing SMX degradation by the Cu-OMS-2/PMS system was further investigated with a quenching experiment,high-resolution mass spec-troscopy,and electron paramagnetic resonance.Results showed that SMX degradation efficiency was enhanced in seawater and tap water,demonstrating the potential application of Cu-OMS-2/PMS system in sewage treatment. 展开更多
关键词 SULFAMETHOXAZOLE manganese oxide octahedral molecular sieve PEROXYMONOSULFATE sewage treatment COPPER
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Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries 被引量:1
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作者 Wentao Qu Yong Cai +1 位作者 Baohui Chen Ming Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期112-122,共11页
Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during t... Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy. 展开更多
关键词 electrochemical activation HETEROINTERFACE manganese dissolution inhibition oxygen defects zinc ion batteries
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Extraction and recycling technologies of cobalt from primary and secondary resources:A comprehensive review
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作者 Yukun Huang Pengxu Chen +5 位作者 Xuanzhao Shu Biao Fu Weijun Peng Jiang Liu Yijun Cao Xiaofeng Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期628-649,共22页
Cobalt has excellent electrochemical,magnetic,and heat properties.As a strategic resource,it has been applied in many hightech products.However,the recent rapid growth of the battery industry has substantially deplete... Cobalt has excellent electrochemical,magnetic,and heat properties.As a strategic resource,it has been applied in many hightech products.However,the recent rapid growth of the battery industry has substantially depleted cobalt resources,leading to a crisis of cobalt resource supply.The paper examines cobalt ore reserves and distribution,and the recent development and consumption of cobalt resources are summarized as well.In addition,the principles,advantages and disadvantages,and research status of various methods are discussed comprehensively.It can be concluded that the use of diverse sources(Cu-Co ores,Ni-Co ores,zinc plant residues,and waste cobalt products)for cobalt production should be enhanced to meet developmental requirements.Furthermore,in recovery technology,the pyro-hydrometallurgical process employs pyrometallurgy as the pretreatment to modify the phase structure of cobalt minerals,enhancing its recovery in the hydrometallurgical stage and facilitating high-purity cobalt production.Consequently,it represents a promising technology for future cobalt recovery.Lastly,based on the above conclusions,the prospects for cobalt are assessed regarding cobalt ore processing and sustainable cobalt recycling,for which further study should be conducted. 展开更多
关键词 cobalt recovery copper-cobalt ore nickel-cobalt ore zinc plant residue waste cobalt products
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Synergism of preintercalated manganese ions and lattice water in vanadium oxide cathodes for high-capacity and long-life Zn-ion batteries
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作者 Mengjing Wu Rongrong Li +3 位作者 Kai Yang Lijiang Yin Weikang Hu Xiong Pu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期709-717,共9页
Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials... Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials.In this work,we present an intercalation mechanism-based cathode materials for AZIB,i.e.the vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural stability.Systematic in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous electrolyte.The demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs. 展开更多
关键词 Zn-ion batteries Vanadium oxide Pre-intercalation Lattice water manganese ion
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The component-activity interrelationship of cobalt-based bifunctional electrocatalysts for overall water splitting:Strategies and performance
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作者 Mingjie Sun Riyue Ge +4 位作者 Sean Li Liming Dai Yiran Li Bin Liu Wenxian Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期453-474,共22页
Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysi... Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications. 展开更多
关键词 cobalt Bifunctional electrocatalysis Water splitting Modification strategies Electrocatalytic performances
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Hot deformation behavior and hot-metal-gas-forming process of V micro-alloyed high manganese steel
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作者 Yong-gang Yang Wang-nan Zuo +4 位作者 Mei Xu Chang-hui Yuan Jiang Chang Lei Qi Zhen-li Mi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第9期2271-2280,共10页
The hot deformation behavior of a newly designed V micro-alloyed high manganese steel(HMnS)was investigated in order to guide the development of the hot-metal-gas-forming process.Single-pass hot compression experiment... The hot deformation behavior of a newly designed V micro-alloyed high manganese steel(HMnS)was investigated in order to guide the development of the hot-metal-gas-forming process.Single-pass hot compression experiments were conducted in the temperature range of 950–1100°C and the strain rate range of 0.05–10 s^(−1),and the stress–strain curves and the corresponding softening mechanism of the V micro-alloyed HMnS were analyzed.Results show that two types of stress–strain curves,representing the work hardening(WH)-dynamic recovery(DRV)-dynamic recrystallization(DRX)mechanism and the WH–DRV mechanism,respectively,occur during the deformation process.Moreover,the WH–DRV–DRX mechanism gradually transforms into the WH–DRV mechanism with the increasing strain rate and decreasing deformation temperature.Two types of constitutive models considering the softening mechanism difference were established and verified by additional hot-deformation experiments.Hot processing map of the HMnS was established and correlated well with the microstructure evolution result.Based on the constitutive models and processing map,the optimal processing parameter range and flow stress of HMnS for the hot-metal-gas-forming were determined. 展开更多
关键词 High manganese steel Hot-metal-gas-forming Deformation behavior Microstructure Softening mechanism
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Structural and magnetic properties of micropolycrystalline cobalt thin films fabricated by direct current magnetron sputtering
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作者 Kerui Song Zhou Li +2 位作者 Mei Fang Zhu Xiao Qian Lei 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期384-394,共11页
Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were investigated.As... Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were investigated.As the sputtering power increases from 15 to 60 W,the Co thin films transition from an amorphous to a polycrystalline state,accompanied by an increase in the intercrystal pore width.Simultaneously,the resistivity decreases from 276 to 99μΩ·cm,coercivity increases from 162 to 293 Oe,and in-plane magnetic aniso-tropy disappears.As the sputtering pressure decreases from 1.6 to 0.2 Pa,grain size significantly increases,resistivity significantly de-creases,and the coercivity significantly increases(from 67 to 280 Oe),which can be attributed to the increase in defect width.Corres-pondingly,a quantitative model for the coercivity of Co thin films was formulated.The polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy,which is primarily attributable to increased microstress. 展开更多
关键词 cobalt thin film magnetron sputtering microstructure electromagnetic properties
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Preparation of Manganese Oxide and Its Adsorption Properties
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作者 贺跃 王海峰 +4 位作者 YANG Pan WANG Song CHEN Xiaoliang YANG Chunyuan 王家伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1031-1040,共10页
The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of ... The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of different oxidants on the morphology,phase composition,surface properties and specific surface area of manganese oxides were investigated.The experimental results show that the diameter of manganese oxide particles prepared with H_(2)O_(2)is the smallest,about 50 nm,and the specific surface area is the largest,63.8764 m^(2)/g.It has the advantages of abundant surface hydroxyl groups,no introduction of other impurities and large adsorption potential.It is most suitable to be used as an oxidant for oxidizing manganese sulfate solution to prepare manganese oxide by in-situ oxidation.Nano manganese oxide prepard by H_(2)O_(2)in-situ oxidation method is used as adsorbent to adsorb cobalt and nickel impurities in manganese sulfate.When the reaction pH is 6,the reaction time is 30min and the amount of adsorbent is 1.0 g,the adsorption rates of cobalt and nickel impurities in 100ml manganese sulfate solution are 97.59%and 97.67%,respectively.The residual amounts of cobalt and nickel meet the industrial process standard of first-class products(Co,Ni w/%≤0.005)of high-purity manganese sulfate(Hg/t4823-2015)for batteries.The study plays a guiding role in the preparation and regulation of manganese oxide,and provides a new method with high efficiency,purity and adsorbent availability for the preparation of high-purity manganese sulfate solution. 展开更多
关键词 manganese oxide in situ oxidation ADSORBENT regulation mechanism PHYSICAL chemical properties
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MOF-Derived Iron-Cobalt Phosphide Nanoframe as Bifunctional Electrocatalysts for Overall Water Splitting
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作者 Yanqi Yuan Kun Wang +5 位作者 Boan Zhong Dongkun Yu Fei Ye Jing Liu Joydeep Dutta Peng Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期312-320,共9页
Transition metal phosphides(TMPs)have emerged as an alternative to precious metals as efficient and low-cost catalysts for water electrolysis.Elemental doping and morphology control are effective approaches to further... Transition metal phosphides(TMPs)have emerged as an alternative to precious metals as efficient and low-cost catalysts for water electrolysis.Elemental doping and morphology control are effective approaches to further improve the performance of TMPs.Herein,Fe-doped CoP nanoframes(Fe-CoP NFs)with specific open cage configuration were designed and synthesized.The unique nano-framework structured Fe-CoP material shows overpotentials of only 255 and 122 mV at 10 mA cm^(−2)for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER),respectively,overwhelming most transition metal phosphides.For overall water splitting,the cell voltage is 1.65 V for Fe-CoP NFs at a current density of 10 mA cm^(−2),much superior to what is observed for the classical nanocubic structures.Fe-CoP NFs show no activity degradation up to 100 h which contrasts sharply with the rapidly decaying performance of noble metal catalyst reference.The superior electrocatalytic performance of Fe-CoP NFs due to abundant accessible active sites,reduced kinetic energy barrier,and preferable*O-containing intermediate adsorption is demonstrated through experimental observations and theoretical calculations.Our findings could provide a potential method for the preparation of multifunctional material with hollow structures and offer more hopeful prospects for obtaining efficient earth-abundant catalysts for water splitting. 展开更多
关键词 ELECTROCATALYSIS hollow structure iron-doped cobalt phosphide MOF overall water splitting
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High-Voltage and Fast-Charging Lithium Cobalt Oxide Cathodes: From Key Challenges and Strategies to Future Perspectives
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作者 Gongrui Wang Zhihong Bi +3 位作者 Anping Zhang Pratteek Das Hu Lin Zhong-Shuai Wu 《Engineering》 SCIE EI CAS CSCD 2024年第6期105-127,共23页
Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable electronics.However,the lithiu... Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable electronics.However,the lithium ion(Li+)-storage performance of the most commercialized lithium cobalt oxide(LiCoO_(2),LCO)cathodes is still far from satisfactory in terms of high-voltage and fast-charging capabilities for reaching the double-high target.Herein,we systematically summarize and discuss high-voltage and fast-charging LCO cathodes,covering in depth the key fundamental challenges,latest advancements in modification strategies,and future perspectives in this field.Comprehensive and elaborated discussions are first presented on key fundamental challenges related to structural degradation,interfacial instability,the inhomogeneity reactions,and sluggish interfacial kinetics.We provide an instructive summary of deep insights into promising modification strategies and underlying mechanisms,categorized into element doping(Li-site,cobalt-/oxygen-site,and multi-site doping)for improved Li+diffusivity and bulkstructure stability;surface coating(dielectrics,ionic/electronic conductors,and their combination)for surface stability and conductivity;nanosizing;combinations of these strategies;and other strategies(i.e.,optimization of the electrolyte,binder,tortuosity of electrodes,charging protocols,and prelithiation methods).Finally,forward-looking perspectives and promising directions are sketched out and insightfully elucidated,providing constructive suggestions and instructions for designing and realizing high-voltage and fast-charging LCO cathodes for next-generation double-high LIBs. 展开更多
关键词 Lithium cobalt oxide High energy/power density Fast-charging HIGH-VOLTAGE Lithium-ion battery
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Modification,application and expansion of electrode materials based on cobalt telluride
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作者 Huilin Fan Yao Dai +7 位作者 Xiaoyun Xue Runguo Zheng Yuan Wang Hamidreza Arandiyan Zhiyuan Wang Zongping Shao Hongyu Sun Yanguo Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期710-737,I0015,共29页
Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overa... Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overall performance of rechargeable batteries heavily depends on their electrode materials.Transition metal tellurides have recently gained significant attention due to their high electrical conductivity and density.Cobalt telluride has received the most extensive research due to its catalytic activity,unique magnetic properties,and diverse composition and crystal structure.Nevertheless,its limited conductivity and significant volume variation contribute to electrode structural deterioration and rapid capacity decline.This review comprehensively summarizes recent advances in rational design and synthesis of modified cobalt telluride-based electrodes,encompassing defect engineering(Te vacancies,cation vacancies,heterointerfaces,and homogeneous interfaces)and composite engineering(derived carbon from precursors,carbon fibers,Mxene,graphene nanosheets,etc.).Particularly,the intricate evolution mechanisms of the conversion reaction process during cycling are elucidated.Furthermore,these modified strategies applied to other transitional metal tellurides,such as iron telluride,nickel telluride,zinc telluride,copper telluride,molybdenum telluride,etc.,are also thoroughly summarized.Additionally,their application extends to emerging aqueous zinc-ion batteries.Finally,potential challenges and prospects are discussed to further propel the development of transition metal tellurides electrode materials for next-generation rechargeable batteries. 展开更多
关键词 Rechargeable batteries Transition metal tellurides cobalt telluride Defect engineering Composite engineering
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Manganese-Catalyzed Ring-Opening C—C Bond Fluorination of Cyclobutanols
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作者 Wang Limei Liu Xiaoyuan +4 位作者 Zan Jincheng Sun Shutao Liu Lei Li Wei Liu Xigong 《有机化学》 SCIE CAS CSCD 北大核心 2024年第7期2333-2340,共8页
Manganese-catalyzed C—C bond cleavage of cyclobutanols has attracted great attention due to the high abundance and cheap and eco-friendly behaviour.A manganese-catalyzed ring-opening C—C bond fluorination of cyclobu... Manganese-catalyzed C—C bond cleavage of cyclobutanols has attracted great attention due to the high abundance and cheap and eco-friendly behaviour.A manganese-catalyzed ring-opening C—C bond fluorination of cyclobutanols is reported.Under mild conditions,the reaction provides a straightforward access to γ-fluorinated ketones using 10 mol% Mn(OAc)_(2) as catalyst and electrophilic fluorination reagent,which was generated in situ from HF·Et 3N and PhIO,as fluorine source.The reaction has an excellent functional-group tolerance and displays a broad substrate scope,affording the corresponding products in 50%~76%yields. 展开更多
关键词 manganese catalysis C—C bond functionalization cyclobutanol FLUORINATION γ-fluorinated ketone
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Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis:Important roles of microstructures and electronic modulation
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作者 Hongyu Gong Guanliang Sun +6 位作者 Wenhua Shi Dongwei Li Xiangjun Zheng Huan Shi Xiu Liang Ruizhi Yang Changzhou Yuan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期1-14,共14页
Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable goal.Herein,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au... Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable goal.Herein,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au nanoparticles(NPs)(denoted as HP-Au@CoxSy@ZIF-67)hybrid is synthesized by low-temperature sulfuration treatment.The well-defined macroporous-mesoporous-microporous structure is obtained based on the combination of polystyrene spheres,as-formed CoxSy nanosheets,and ZIF-67 frameworks.This novel three-dimensional hierarchical structure significantly enlarges the three-phase interfaces,accelerating the mass transfer and exposing the active centers for oxygen evolution reaction.The electronic structure of Co is modulated by Au through charge transfer,and a series of experiments,together with theoretical analysis,is performed to ascertain the electronic modulation of Co by Au.Meanwhile,HP-Au@CoxSy@ZIF-67 catalysts with different amounts of Au were synthesized,wherein Au and NaBH4 reductant result in an interesting“competition effect”to regulate the relative ratio of Co^(2+)/Co^(3+),and moderate Au assists the electrochemical performance to reach the highest value.Consequently,the optimized HP-Au@CoxSy@ZIF-67 exhibits a low overpotential of 340 mV at 10 mA cm^(-2)and a Tafel slope of 42 mV dec-1 for OER in 0.1 M aqueous KOH,enabling efficient water splitting and Zn-air battery performance.The work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts. 展开更多
关键词 Au nanoparticles cobalt sulfide electronic modulation hierarchical porous structure oxygen evolution reaction
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Enhanced recovery of high-purity Fe powder from iron-rich electrolytic manganese residue by slurry electrolysis
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作者 Wenxing Cao Jiancheng Shu +5 位作者 Jiaming Chen Zihan Li Songshan Zhou Shushu Liao Mengjun Chen Yong Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期531-538,共8页
Iron-rich electrolytic manganese residue(IREMR)is an industrial waste produced during the processing of electrolytic metal manganese,and it contains certain amounts of Fe and Mn resources and other heavy metals.In thi... Iron-rich electrolytic manganese residue(IREMR)is an industrial waste produced during the processing of electrolytic metal manganese,and it contains certain amounts of Fe and Mn resources and other heavy metals.In this study,the slurry electrolysis technique was used to recover high-purity Fe powder from IREMR.The effects of IREMR and H2SO4 mass ratio,current density,reaction temper-ature,and electrolytic time on the leaching and current efficiencies of Fe were studied.According to the results,high-purity Fe powder can be recovered from the cathode plate,and the slurry electrolyte can be recycled.The leaching efficiency,current efficiency,and purity of Fe reached 92.58%,80.65%,and 98.72wt%,respectively,at a 1:2.5 mass ratio of H2SO4 and IREMR,reaction temperature of 60℃,electric current density of 30 mA/cm^(2),and reaction time of 8 h.In addition,vibrating sample magnetometer(VSM)analysis showed that the coercivity of electrolytic iron powder was 54.5 A/m,which reached the advanced magnetic grade of electrical pure-iron powder(DT4A coercivity standard).The slurry electrolytic method provides fundamental support for the industrial application of Fe resource recovery in IRMER. 展开更多
关键词 iron-rich electrolytic manganese residue slurry electrolysis high-purity iron powder leaching efficiency current efficiency
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CoS Nanosheets Coated with Dopamine-Derived Carbon Standing on Carbon Fiber Cloth as Binder-Free Anode for Li-ion Batteries
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作者 Lianyuan Ji Mingchen Shi +1 位作者 Zengkai Feng Hui Yang 《Journal of Renewable Materials》 EI CAS 2024年第2期259-274,共16页
Cobalt sulphides attract much attention as anode materials for Li-ion batteries(LIBs).However,its poor conductivity,low initial column efficiency and large volume changes during cycling have hindered its further devel... Cobalt sulphides attract much attention as anode materials for Li-ion batteries(LIBs).However,its poor conductivity,low initial column efficiency and large volume changes during cycling have hindered its further development.Herein,novel interlaced CoS nanosheets were firstly prepared on Carbon Fiber Cloth(CFC)by two hydrothermal reactions followed with carbon coating via carbonizing dopamine(CoS NS@C/CFC).As a freestanding anode,the nanosheet structure of CoS not only accommodates the volume variation,but also provides a large interface area to proceed the charge transfer reaction.In addition,CFC works as both a three-dimensional skeleton and an active substance which can further improve the areal capacity of the resulting electrode.Furthermore,the coated carbon combined with the CFC work as a 3D conductive network to facilitate the electron conduction.The obtained CoS NS@C/CFC,and the contrast sample prepared with the same procedure but without carbon coating(CoS NS/CFC),are characterized with XRD,SEM,TEM,XPS and electrochemical measurements.The results show that the CoS NS@C/CFC possesses much improved electrochemical performance due to the synergistic effect of nanosheet CoS,the coated carbon and the CFC substrate,exhibiting high initial columbic efficiency(~87%),high areal capacity(2.5 at 0.15 mA cm−2),excellent rate performance(1.6 at 2.73 mA cm−2)and improved cycle stability(87.5%capacity retention after 300 cycles).This work may provide a new route to explore freestanding anodes with high areal specific capacity for LIBs. 展开更多
关键词 Lithium-ion battery cobalt sulfide carbon coating carbon fiber cloth freestanding anode
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The Influence of CO_(2) Cured Manganese Slag on the Performance and Mechanical Properties of Ultra-High Performance Concrete
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作者 Ligai Bai Guihua Yang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1717-1730,共14页
The presence of toxic elements in manganese slag(MSG)poses a threat to the environment due to potential pollution.Utilizing CO_(2) curing on MS offers a promising approach to immobilize toxic substances within this ma... The presence of toxic elements in manganese slag(MSG)poses a threat to the environment due to potential pollution.Utilizing CO_(2) curing on MS offers a promising approach to immobilize toxic substances within this material,thereby mitigating their release into the natural surroundings.This study investigates the impact of CO_(2) cured MS on various rheological parameters,including slump flow,plastic viscosity(η),and yield shear stress(τ).Additionally,it assesses flexural and compressive strengths(f_(t) and f_(cu)),drying shrinkage rates(DSR),durability indicators(chloride ion migration coefficient(CMC),carbonization depth(CD)),and the leaching behavior of heavy metal elements.Microscopic examination via scanning electron microscopy(SEM)is employed to elucidate the underlying mechanisms.The results indicate that CO_(2) curing significantly enhances the slump flow of ultra-high performance concrete(UHPC)by up to 51.2%.Moreover,it reduces UHPC’sηandτby rates ranging from 0%to 52.7%and 0%to 40.2%,respectively.The DSR exhibits a linear increase corresponding to the mass ratio of CO_(2) cured MS.Furthermore,CO_(2) curing enhances both f_(t) and f_(cu) of UHPC by up to 28.7%and 17.6%,respectively.The electrical resistance is also improved,showing an increase of up to 53.7%.The relationship between mechanical strengths and electrical resistance follows a cubic relationship.The CO_(2) cured MS demonstrates a notable decrease in the CMC and CD by rates ranging from 0%to 52.6%and 0%to 26.1%,respectively.The reductions of leached chromium(Cr)and manganese(Mn)are up to 576.3%and 1312.7%,respectively.Overall,CO_(2) curing also enhances the compactness of UHPC,thereby demonstrating its potential to improve both mechanical and durability properties. 展开更多
关键词 CO_(2)curing manganese slag steel fibers mechanical strengths salt action
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刚果(金)SICOMINES难选高氧化率铜钴矿工艺试验
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作者 罗帅 范海宝 张自旭 《现代矿业》 CAS 2024年第6期110-115,共6页
为了高效回收利用高氧化率铜钴矿石,针对刚果(金)SICOMINES矿区铜矿石氧化率高、矿石回收效果不理想等问题,进行了浮选+磁选工艺试验研究。浮选阶段以硫氢化钠为硫化剂,戊基黄药为捕收剂,2^(#)油为起泡剂,磁选阶段采用1粗1精1扫磁选流程... 为了高效回收利用高氧化率铜钴矿石,针对刚果(金)SICOMINES矿区铜矿石氧化率高、矿石回收效果不理想等问题,进行了浮选+磁选工艺试验研究。浮选阶段以硫氢化钠为硫化剂,戊基黄药为捕收剂,2^(#)油为起泡剂,磁选阶段采用1粗1精1扫磁选流程,最终得到了铜、钴品位分别为60.35%、0.10%,铜、钴回收率分别为21.93%、0.44%的硫化铜精矿;铜、钴品位分别为14.27%、0.66%,铜、钴回收率分别为48.87%、27.95%的氧化铜精矿;铜、钴品位分别为4.38%、0.34%,铜、钴回收率分别为8.53%、8.28%的浮选钴精矿。铜、钴品位分别为2.25%、0.32%,铜、钴回收率分别为5.84%、10.29%的磁选精矿。硫化铜精矿、氧化铜精矿、浮选钴精矿和磁选精矿合计铜总回收率为85.17%,钴总回收率为46.96%,实现了高氧化率矿石的高效回收。 展开更多
关键词 高氧化率铜钴矿 浮选 磁选
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Influence of Triarylamine and Indoline as Donor on Photovoltaic Performance of Dye-Sensitized Solar Cells Employing Cobalt Redox Shuttle
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作者 张月 王志辉 +3 位作者 郝玉杰 武全萍 梁茂 薛松 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期91-100,I0002,共11页
Two organic dyes XSS1 and XS52 derivated from triarylamine and indoline are synthesized for dye-sensitized solar ceils (DSCs) employing cobalt and iodine redox shuttles. The effects of dye structure upon the photoph... Two organic dyes XSS1 and XS52 derivated from triarylamine and indoline are synthesized for dye-sensitized solar ceils (DSCs) employing cobalt and iodine redox shuttles. The effects of dye structure upon the photophysical, electro-chemical characteristics and cell perfor- mance are investigated. XS51 with four hexyloxyl groups on triarylamine performs better steric hindrance and an improvement of photovoltage. X852 provides higher short-circuit photocurrent density due to the strong electron-donating capability of indoline unit. The results from the redox electrolyte on cell performances indicate that the synthesized dyes are more suitable for tris(1,10-phenanthroline)cobalt(II/III) redox couple than I-/I3- redox couple in assembling DSCs. Application of X852 in the cobalt electrolyte yields a DSC with an overall power conversion efficiency of 6.58% under AM 1.5 (100 mW/cm2) irradiation. 展开更多
关键词 Dye-sensitized solar cells INDOLINE TRIARYLAmine PHOTOVOLTAIC cobalt redoxshuttle
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