La^3＋掺杂NiCo层状双金属氢氧化物纳米片的合成及其电化学性能  

La^(3+)-doped NiCo Layered Double Hydroxide Nanosheets and Their Supercapacitive Performance

作　　者：李宫 陈昆峰[2] 金京一[1] 薛冬峰[2] 

机构地区：[1]延边大学化学系,吉林延吉133002 [2]中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,长春130022

出　　处：《应用化学》2017年第1期71-75,共5页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金项目(91434118,21521092);中国科学院国际合作局对外合作重点项目(121522KYS820150009);吉林省科技发展计划项目(20160520002JH)~~

摘　　要：稀土离子La^(3+)掺杂的NiCo层状双金属氢氧化物纳米片具有高的超级电容器性能,比容量达到1115 F/g(1A/g)、倍率性能为517 F/g(30 A/g)。研究表明,La^(3+)离子掺杂不改变NiCo层状双金属氢氧化物晶体结构,但会显著影响其电子和离子传导特性,从而改变其电化学性能。根据离子电负性标度,La^(3+)(1.327)和Co^(2+)(1.377)离子的电负性值最接近,掺杂La^(3+)会优先取代Co^(2+)离子位置。由于La^(3+)离子的尺寸作用(106 pm),使得最优掺杂比例较小仅为0.26%,电化学结果表明较少的La^(3+)掺杂比例依然会显著调节NiCo层状双金属氢氧化物的电子/离子输运性质。NiCo layered double hydroxides（ NiCo-LDHs） are important electrode materials in batteries and supercapacitors,due to its layered structure and controllable ratio and kind of metal ions. In this paper,we studied the effect of La^3＋ions on the crystal structures and electrochemical performances of NiCo-LDHs.According to ionic electronegativity,the values of La^3＋（ 1. 327） and Co^2＋（ 1. 377） are similar,leading to the replace of Co^2＋by La^3＋in La^3＋-doped NiCo-LDHs. La^3＋-doped NiCo-LDHs show high specific capacitance and rate performance,1115 F/g at 1 A/g and 517 F/g at 30 A/g,respectively. XRD,FTIR and SEM prove that La^3＋doping does not change the structures of NiCo-LDHs. However,CV and electrochemical impendence spectrum confirms that the nature of electron or ion transfer is adjusted by La^3＋doping. Owing to the size effect of La^3＋ions,the optimized ratio of La doping is 0. 26%. La^3＋ions doping in electrode materials can be a promising method to change their nature of electron or ion transfer（ electron or ion conductivity）.

关 键 词：层状氢氧化物 稀土离子 掺杂 超级电容器 

分 类 号：O613[理学—无机化学]