The octahedral tunnel-like three-dimensional(3D)structure of V_(2)O_(3)enables fast metal ion(de)intercalation and high capacity in aqueous zinc-ion batteries(ZIBs),but suffers from phase transition-induced structural...The octahedral tunnel-like three-dimensional(3D)structure of V_(2)O_(3)enables fast metal ion(de)intercalation and high capacity in aqueous zinc-ion batteries(ZIBs),but suffers from phase transition-induced structural degradation and capacity fading.Herein,we demonstrate that the undesirable phase transition of V_(2)O_(3)can be effectively suppressed through a new La^(3+)doping strategy and its implementation as a robust ZIBs cathode.The introduced La^(3+)ions not only can increase cell volume and expand ion channels of V_(2)O_(3)but also offer plentiful Zn^(2+)storage sites and promote the transport of Zn^(2+)ions and electrons.In particular,the doping of La^(3+)maintains the octahedral tunnel structure of V_(2)O_(3)and prevents its phase transition during(dis)charge,which improves the cycle stability of the V_(2)O_(3)cathode in ZIBs.By virtue of the above favorable factors,La-doped V_(2)O_(3)electrode presents an impressive discharge capacity of632.1 m Ah g^(-1)at 0.1 A g^(-1)after 100 cycles with a capacity retention up to 93.1%.Even at 10 A g^(-1),its discharge capacity remains at 342.7 mAh g^(-1)after 1000 cycles with a capacity attenuation of solely0.0069%per cycle.This work establishes rare-earth cation doping as a universal paradigm to reconcile structural stability and multi-electron redox activity in high-capacity battery electrodes.展开更多
Conversion-alloy-type anodes have attracted considerable attention in potassium-ion batteries due to their high theoretical capacities,but the inferior stability hinders their potential applications.Generally,the fail...Conversion-alloy-type anodes have attracted considerable attention in potassium-ion batteries due to their high theoretical capacities,but the inferior stability hinders their potential applications.Generally,the failure mechanism of conversion-alloy anodes is ascribed to volume expansion or the shuttle effect,which,however,fails to adequately explain their characteristic electrochemical behavior:an initial rapid drop and then a gradual decline in capacity.Herein,by combining electrochemical characterizations with multi-scale microscopies,spectroscopy,and theoretical calculations,we systematically analyze the failure mechanism of Bi_(2)Te_(3),a typical conversion-alloy anode.The failure processes and mechanisms are identified into two stages:(1)the rapid capacity fading dominated by the shuttle effect in the first several cycles and(2)the gradual material deactivation and capacity decline due to solid-electrolyte interphase accumulation in the following cycles.Furthermore,in response to these failure mechanisms,an elaborate design of Bi_(2)Te_(3)-based electrode featuring ultrafine nanoparticles and carbon encapsulation is presented,which exhibits prominent capability in avoiding the above negative effects and substantially enhancing cycling stability.This study reveals the failure mechanism of conversion-alloy anode throughout its entire life cycle,and the gained insight may lead to targeted optimization strategies for stable high-capacity electrodes.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51962027,and 52262039)the Fundamental Research Funds for Inner Mongolia University of Science&Technology(No.2024QNJS071,2023QNJS052 and 2024QNJS064)+2 种基金the Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(No.NJYT24002)the Central Guidance Fund for Local Scientific and Technological Development(2024ZY0012)the Ordos Higher Education Institutions Scientific Research Innovation Project(KYLJ25Z004)。
文摘The octahedral tunnel-like three-dimensional(3D)structure of V_(2)O_(3)enables fast metal ion(de)intercalation and high capacity in aqueous zinc-ion batteries(ZIBs),but suffers from phase transition-induced structural degradation and capacity fading.Herein,we demonstrate that the undesirable phase transition of V_(2)O_(3)can be effectively suppressed through a new La^(3+)doping strategy and its implementation as a robust ZIBs cathode.The introduced La^(3+)ions not only can increase cell volume and expand ion channels of V_(2)O_(3)but also offer plentiful Zn^(2+)storage sites and promote the transport of Zn^(2+)ions and electrons.In particular,the doping of La^(3+)maintains the octahedral tunnel structure of V_(2)O_(3)and prevents its phase transition during(dis)charge,which improves the cycle stability of the V_(2)O_(3)cathode in ZIBs.By virtue of the above favorable factors,La-doped V_(2)O_(3)electrode presents an impressive discharge capacity of632.1 m Ah g^(-1)at 0.1 A g^(-1)after 100 cycles with a capacity retention up to 93.1%.Even at 10 A g^(-1),its discharge capacity remains at 342.7 mAh g^(-1)after 1000 cycles with a capacity attenuation of solely0.0069%per cycle.This work establishes rare-earth cation doping as a universal paradigm to reconcile structural stability and multi-electron redox activity in high-capacity battery electrodes.
基金supported by the National Natural Science Foundation of China(Grant Nos.52172240)the Natural Science Foundation of Jiangsu Province of China(BK20240591)the General Project of Education Department of Jiangsu Province(24KJB480008)。
文摘Conversion-alloy-type anodes have attracted considerable attention in potassium-ion batteries due to their high theoretical capacities,but the inferior stability hinders their potential applications.Generally,the failure mechanism of conversion-alloy anodes is ascribed to volume expansion or the shuttle effect,which,however,fails to adequately explain their characteristic electrochemical behavior:an initial rapid drop and then a gradual decline in capacity.Herein,by combining electrochemical characterizations with multi-scale microscopies,spectroscopy,and theoretical calculations,we systematically analyze the failure mechanism of Bi_(2)Te_(3),a typical conversion-alloy anode.The failure processes and mechanisms are identified into two stages:(1)the rapid capacity fading dominated by the shuttle effect in the first several cycles and(2)the gradual material deactivation and capacity decline due to solid-electrolyte interphase accumulation in the following cycles.Furthermore,in response to these failure mechanisms,an elaborate design of Bi_(2)Te_(3)-based electrode featuring ultrafine nanoparticles and carbon encapsulation is presented,which exhibits prominent capability in avoiding the above negative effects and substantially enhancing cycling stability.This study reveals the failure mechanism of conversion-alloy anode throughout its entire life cycle,and the gained insight may lead to targeted optimization strategies for stable high-capacity electrodes.
