混合氨-碱沉淀剂制备Ni(OH)_2/还原氧化石墨烯复合材料及其电化学性能  

Ammonia-alkali mixed precipitant route for preparation of Ni(OH)_2/reduced graphene oxide composites and electrochemical performance

作　　者：于慧颖[1] 赫文秀[1] 张永强[1] 李兴盛[1] 李子庆[1] 

机构地区：[1]内蒙古科技大学化学与化工学院,包头014010

出　　处：《复合材料学报》2017年第7期1589-1595,共7页Acta Materiae Compositae Sinica

基　　金：内蒙古青年科技英才计划(NJYT-14-A08);内蒙古自然科学基金(2014MS0523;2015MS0208);包头市科技计划(2015C2004-1)

摘　　要：利用简单易行的化学沉淀-回流法制备了Ni(OH)_2/还原氧化石墨烯(RGO)复合材料,研究了不同混合氨-碱沉淀剂对复合材料电化学性能的影响。采用XRD、拉曼光谱(Raman)和SEM表征Ni(OH)_2/RGO复合材料的微观结构和形貌。当以NH_3·H_2O-NaOH作为沉淀剂时,Ni(OH)_2/RGO复合材料中β-Ni(OH)_2纳米片均匀分散在石墨烯片层之间,形成相互插层结构。利用循环伏安(CV)、恒电流充放电(GCD)和电化学交流阻抗(EIS)测试了复合电极材料的电化学性能。研究结果表明:放电倍率为0.2C时,Ni(OH)_2/RGO复合电极材料的放电比容量达到344.8mAh/g,比β-Ni(OH)2的放电比容量高出约29%;5C时放电比容量为274.5mAh/g,经过50个循环,容量保持率为98.8%,呈现出良好的倍率性能和循环性能。Nickel hydroxide/reduced graphene oxide（Ni（OH）2/RGO）composites were synthesized by simple and practicable chemical precipitation-reflux method.The influence of different ammonia-alkali mixed precipitant on electrochemical performance of composite materials was researched.The microstructure and morphology of the Ni（OH）2/RGO composites were characterized by XRD,Raman spectra and SEM.The synthesized Ni（OH）2/RGO composite shows thatβ-Ni（OH）2 nano sheets are homogeneously dispersed and inserted into RGO sheets,thus mutually inserted structure is formed using ammonium hydroxide-sodium hydroxide as precipitant.The electrochemical characteristics of composite electrode materials were tested by cyclic voltammetry（CV）,galvanostatic charge/discharge（GCD）and electrochemical impedance spectroscopy（EIS）.The results show that the prepared Ni（OH）2/RGO composite exhibits a high discharge specific capacity of 344.8mAh/g at 0.2 Crate,and is 29% higher than the specific capacity of β-Ni（OH）2.The discharge specific capacity of theβ-Ni（OH）2/RGO composite is274.5mAh/g at 5 Crate.Moreover,98.8% of the initial specific capacity of the composite is maintained after 50 cycle test.Ni（OH）2/RGO composite displays a better rate capability and cycle performance as electrode material.

关 键 词：混合氨-碱沉淀剂 Β-NI(OH)2 还原氧化石墨烯 电极材料 电化学性能 

分 类 号：TQ150.7[化学工程—电化学工业]