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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。
The Ni (OH) 2 / RGO composite was prepared by simple chemical precipitation-reflux method. The effects of different mixed ammonia-base precipitants on the electrochemical properties of the composites were studied. The microstructure and morphology of Ni (OH) 2 / RGO composites were characterized by XRD, Raman spectroscopy and SEM. When NH_3 · H_2O-NaOH was used as the precipitating agent, the β-Ni (OH) _2 nanosheets in Ni (OH) 2 / RGO composites were uniformly dispersed between the graphene sheets to form intercalating structures. The electrochemical properties of the composite electrode materials were tested by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The results show that the discharge capacity of Ni (OH) 2 / RGO composite electrode reaches 344.8mAh / g at a discharge rate of 0.2C, which is about 29% higher than the discharge capacity of β-Ni (OH) When the specific discharge capacity of 274.5mAh / g, after 50 cycles, the capacity retention rate of 98.8%, showing good rate performance and cycle performance.