摘要
Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of many nanoflakes,are about 2-3μm in diameter.The length of the NiO flakes,having clear edges,is about 500-700 nm,while the thickness is only about 40-50 nm.This indicates that the NiO microspheres possess a hierarchical structure that can provide porous channels to facilitate the transmission of both electrons and electrolyte ions.NiO microspheres exhibit a high specific capacitance of about 1340 F/g at a current density of 1 A/g and high capacitance retention about 96.5%after 1000 cycles.What’s more,the conductive mechanism of nickel oxide for electrochemical capacitor electrodes was also studied.
采用水热合成-煅烧的方法,通过自组装过程,制备具有微纳分级结构的NiO中空微球。所制备的微纳分级结构NiO微球由许多NiO纳米片相互堆叠而成,颗粒粒径大约为2~3μm。NiO纳米片边缘清晰,片长约为500~700 nm,厚度仅为40~50 nm。这种独特的微纳分级结构使得NiO材料具有相互贯通的孔道,这有利于电解质离子和电子的扩散和迁移。所制备的微纳分级结构NiO电极材料具有优越的电化学性能,在1 A/g的电流密度下比电容可达到1340 F/g,且循环1000次后,容量保持率为96.5%。同时,对氧化镍电化学电容器的导电机理进行探究。
基金
Project(51274248)supported by the National Natural Science Foundation of China
Project(201FA31440)supported by the International S&T Cooperation Program of China
