The indium tin oxide scrap (ITOS) was mechanically activated by a stirring ball mill and subsequently studied for the leaching behavior and kinetics of extracting indium from ITOS in hydrochloric acid solution. The X-...The indium tin oxide scrap (ITOS) was mechanically activated by a stirring ball mill and subsequently studied for the leaching behavior and kinetics of extracting indium from ITOS in hydrochloric acid solution. The X-ray diffraction (XRD) analysis showed that MA caused the decrease in crystalline phase and increase in lattice distortion. The effects of reaction temperature and hydrochloric acid concentration on the leaching rate of indium were also investigated, which showed that the indium extraction from ITOS had significant dependency on temperature and HCl concentration. The equal-recovery method was used for kinetics analysis. When ITOS was mechanically activated for 15 and 30 min, the apparent activation energy decreased from 90.6 kJ/mol to 70.3 and 53.0 kJ/mol, respectively, which indicated that MA could enhance the reactivity of ITOS and accelerated the reaction. The reaction orders of extracting indium from the nonactivated, milled for 15 and 30 min ITOS with respect to HCl concentration were 2.30, 1.44, and 1.31, respectively.展开更多
深入理解电极的电化学反应过程和机理对高性能电极材料的设计、开发至关重要.本文研究了正交相V2O5单晶纳米线在1.0–4.0 V(vs.Na/Na^(+))电位窗口下的钠离子存储行为和机理.该单晶纳米线在首次放电/充电循环中表现出高的不可逆容量损失...深入理解电极的电化学反应过程和机理对高性能电极材料的设计、开发至关重要.本文研究了正交相V2O5单晶纳米线在1.0–4.0 V(vs.Na/Na^(+))电位窗口下的钠离子存储行为和机理.该单晶纳米线在首次放电/充电循环中表现出高的不可逆容量损失,在随后的循环中表现出良好的循环稳定性.在100 mA g^(-1)电流密度下,其初始放电和充电比容量分别为217和88 mA hg^(-1),对应的库伦效率仅为40.5%.经过100次循环后,其可逆放电容量保持在78 mA hg^(-1),与第二次放电容量相比其每圈循环衰减率仅为0.09%.采用循环伏安(CV)、非原位X-射线衍射(ex-situ XRD)、扫描电镜(SEM)和透射电镜(TEM)表征,分析了正交相V_(2)O_(5)单晶纳米线的钠离子存储机理,发现V_(2)O_(5)单晶纳米线在首次循环中的高不可逆容量损失主要是因为其在放电过程中生成了钠离子无法脱出的α'-Nax V_(2)O_(5)(0.02<x<0.88)单晶相.该α'-Na0.88 V_(2)O_(5)可通过单相(固溶体)反应可逆地嵌入和脱出钠离子,因此在后续循环中表现出优异的稳定性.采用恒电流间歇电位滴定(GITT)分析发现,α'-Nax V_(2)O_(5)中钠离子扩散系数值为10^(12)-10^(-11.5)cm^(2)s^(-1).展开更多
文摘The indium tin oxide scrap (ITOS) was mechanically activated by a stirring ball mill and subsequently studied for the leaching behavior and kinetics of extracting indium from ITOS in hydrochloric acid solution. The X-ray diffraction (XRD) analysis showed that MA caused the decrease in crystalline phase and increase in lattice distortion. The effects of reaction temperature and hydrochloric acid concentration on the leaching rate of indium were also investigated, which showed that the indium extraction from ITOS had significant dependency on temperature and HCl concentration. The equal-recovery method was used for kinetics analysis. When ITOS was mechanically activated for 15 and 30 min, the apparent activation energy decreased from 90.6 kJ/mol to 70.3 and 53.0 kJ/mol, respectively, which indicated that MA could enhance the reactivity of ITOS and accelerated the reaction. The reaction orders of extracting indium from the nonactivated, milled for 15 and 30 min ITOS with respect to HCl concentration were 2.30, 1.44, and 1.31, respectively.
基金financially supported by the National Natural Science Foundation of China (51664012)Guangxi Natural Science Foundation (2017GXNSFAA198117 and2015GXNSFGA139006)the Technology Major Project of Guangxi(AA19046001)
文摘深入理解电极的电化学反应过程和机理对高性能电极材料的设计、开发至关重要.本文研究了正交相V2O5单晶纳米线在1.0–4.0 V(vs.Na/Na^(+))电位窗口下的钠离子存储行为和机理.该单晶纳米线在首次放电/充电循环中表现出高的不可逆容量损失,在随后的循环中表现出良好的循环稳定性.在100 mA g^(-1)电流密度下,其初始放电和充电比容量分别为217和88 mA hg^(-1),对应的库伦效率仅为40.5%.经过100次循环后,其可逆放电容量保持在78 mA hg^(-1),与第二次放电容量相比其每圈循环衰减率仅为0.09%.采用循环伏安(CV)、非原位X-射线衍射(ex-situ XRD)、扫描电镜(SEM)和透射电镜(TEM)表征,分析了正交相V_(2)O_(5)单晶纳米线的钠离子存储机理,发现V_(2)O_(5)单晶纳米线在首次循环中的高不可逆容量损失主要是因为其在放电过程中生成了钠离子无法脱出的α'-Nax V_(2)O_(5)(0.02<x<0.88)单晶相.该α'-Na0.88 V_(2)O_(5)可通过单相(固溶体)反应可逆地嵌入和脱出钠离子,因此在后续循环中表现出优异的稳定性.采用恒电流间歇电位滴定(GITT)分析发现,α'-Nax V_(2)O_(5)中钠离子扩散系数值为10^(12)-10^(-11.5)cm^(2)s^(-1).