Zhu Guozhen, Yang Qihao, Yang Zhen, Che Renchao
Institute of Advanced Materials, Jiangxi Normal University, Nanchang, Jiangxi 330022, P. R. China.
Laboratory of Advanced Materials, Fudan University, Shanghai 200438, P. R. China.
Langmuir. 2023 Feb 28;39(8):3094-3101. doi: 10.1021/acs.langmuir.2c03187. Epub 2023 Feb 17.
Porous hollow CoO microspheres wrapped with graphene oxide were synthesized by a step solvothermal method and subsequent heat treatment. Benefiting from the design of special porous hollow microspheres, the effective specific surface area was greatly increased, the sufficient contact between the porous hollow CoO microspheres and electrolyte was achieved, and then a charge specific capacity of 888.59 mA h g was gained. Meanwhile, partial stress from the charging/discharging process was greatly relieved due to the abundant pores and hollow structure, excellent cycling stability was realized, and the charge specific capacity of the 1000th cycle was 465.75 mA h g at 5 C (1 C = 890 mA g). In addition, the conductivity of CoO microspheres was effectively improved due to the tight package of graphene oxide to CoO microspheres, and superior rate performance was attained (280.99 mA h g at 10 C).
采用分步溶剂热法并随后进行热处理，合成了包裹有氧化石墨烯的多孔中空CoO微球。受益于特殊多孔中空微球的设计，有效比表面积大大增加，多孔中空CoO微球与电解质之间实现了充分接触，进而获得了888.59 mA h g的充电比容量。同时，由于丰富的孔隙和中空结构，充放电过程中的部分应力得到极大缓解，实现了优异的循环稳定性，在5 C（1 C = 890 mA g）下第1000次循环的充电比容量为465.75 mA h g。此外，由于氧化石墨烯对CoO微球的紧密包裹，CoO微球的电导率得到有效提高，并获得了优异的倍率性能（在10 C下为280.99 mA h g）。
