Tin phosphide(Sn_(4)P_(3))is a promising anode material for sodium-ion batteries because of its relatively large theoretical capacity,appropriate Na^(+) alloying potential,and good cyclic stability.Herein,the Sn_(4)P_...Tin phosphide(Sn_(4)P_(3))is a promising anode material for sodium-ion batteries because of its relatively large theoretical capacity,appropriate Na^(+) alloying potential,and good cyclic stability.Herein,the Sn_(4)P_(3) embedded into a carbon matrix with good rate performance and long cycle life is reported.The Sn_(4)P_(3)-C composite exhibits excellent rate performance(540 mAh g^(-1) at 5 A g^(-1))and the highest reversible capacity(844 mAh g^(-1) at 0.5 A ^(g-1))among Sn4P3-based anodes reported so far.Its reversible capacity is as high as 705 mAh g^(-1) even after 100 cycles at 0.5 A g^(-1).Besides,its initial Coulomb efficiency can reach 85.6%,with the average Coulomb efficiency exceeding 99.75%from the 3rd to 100th cycles.Na_(2)C_(6)O_(6) is firstly used as a cathode when Sn_(4)P_(3) acts as anode,and the Na-Sn_(4)P_(3)-C//Na_(2)C_(6)O_(6) full cell shows excellent electrochemical performance.These results demonstrate that the Sn_(4)P_(3)-C composite prepared in this work displays high-rate capability and superior cyclic performance,and thus is a potential anode for sodium ion batteries.展开更多
MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compound...MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compounds undergo during cycling affects their performance and limits practical applications.The present work demonstrates a novel approach to limiting the volume changes of active materials.This effect is based on mechanical support from an intimate interface generated in situ via the reaction between MgH_(2) and Ti within the electrode prior to lithiation to form Mg and TiH_(2).The resulting Mg can be transformed back to MgH_(2) by reaction with LiH during delithiation.In addition,the TiH_(2) improves the reaction kinetics of MgH_(2) and enhances electrochemical performance.The intimate interface produced in this manner is found to improve the electrochemical properties of a MgH_(2)-Ti-LiH electrode.An exceptional reversible capacity of 800 mAh/g is observed even after 200 cycles with a high current density of 1 mA/cm^(2) and a high proportion of active material(90 wt.%)at an operation temperature of 120℃.This study therefore showcases a new means of improving the performance of electrodes by limiting the volume changes of active materials.展开更多
基金supported by the Elements Strategy Initiative for Catalysts and Batteries,MEXT,Japan(Grant Number JPMXP0112101003).
文摘Tin phosphide(Sn_(4)P_(3))is a promising anode material for sodium-ion batteries because of its relatively large theoretical capacity,appropriate Na^(+) alloying potential,and good cyclic stability.Herein,the Sn_(4)P_(3) embedded into a carbon matrix with good rate performance and long cycle life is reported.The Sn_(4)P_(3)-C composite exhibits excellent rate performance(540 mAh g^(-1) at 5 A g^(-1))and the highest reversible capacity(844 mAh g^(-1) at 0.5 A ^(g-1))among Sn4P3-based anodes reported so far.Its reversible capacity is as high as 705 mAh g^(-1) even after 100 cycles at 0.5 A g^(-1).Besides,its initial Coulomb efficiency can reach 85.6%,with the average Coulomb efficiency exceeding 99.75%from the 3rd to 100th cycles.Na_(2)C_(6)O_(6) is firstly used as a cathode when Sn_(4)P_(3) acts as anode,and the Na-Sn_(4)P_(3)-C//Na_(2)C_(6)O_(6) full cell shows excellent electrochemical performance.These results demonstrate that the Sn_(4)P_(3)-C composite prepared in this work displays high-rate capability and superior cyclic performance,and thus is a potential anode for sodium ion batteries.
基金supported in part by JSPS KAKENHI grants (nos. JP21K05243 and JP22H04621grants-in-aid for Scientific Research on Innovative Areas “Interface Ionics”)+1 种基金by a JST grant (no. JPMJFS2132,for the establishment of university fellowships toward the creation of science technology innovation)by the Suzuki foundation
文摘MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compounds undergo during cycling affects their performance and limits practical applications.The present work demonstrates a novel approach to limiting the volume changes of active materials.This effect is based on mechanical support from an intimate interface generated in situ via the reaction between MgH_(2) and Ti within the electrode prior to lithiation to form Mg and TiH_(2).The resulting Mg can be transformed back to MgH_(2) by reaction with LiH during delithiation.In addition,the TiH_(2) improves the reaction kinetics of MgH_(2) and enhances electrochemical performance.The intimate interface produced in this manner is found to improve the electrochemical properties of a MgH_(2)-Ti-LiH electrode.An exceptional reversible capacity of 800 mAh/g is observed even after 200 cycles with a high current density of 1 mA/cm^(2) and a high proportion of active material(90 wt.%)at an operation temperature of 120℃.This study therefore showcases a new means of improving the performance of electrodes by limiting the volume changes of active materials.
