A laser synthesis of vanadium oxide bonded graphene for high-rate supercapacitors

• 作 者: Jun Tang Linfei Zhang Xiongwei Zhong Xinghui Wang Feng Pan Baomin Xu
• 机 构: School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhe
• 出 处: 能源化学
• 发表日期: 2020年10期
• 关键词: Supercapacitors Restacking Vanadium oxides Laser reduced graphene High rate

Graphene is a type of promising electrode material for high-energy and high-power density supercapacitors,but its electrochemical performance is greatly Iimited by the restacking problem.In this work,we reported a facile approach to synthesis graphene with chemically bonded vanadium oxide (VOx) nanoparticles and demonstrated that chemically-bonded VOx nanoparticles can effectively prevent the graphene sheets from restacking and hence improve the electrochemical performance.The capacitance of VOx-bonded graphene increases to 272 F/g compared to 183 F/g of pristine graphene in 1 M H3PO4 aqueous electrolyte at 2 A/g.The VOx-bonded graphene also showed improved rate capability in both H3PO4 and ionic liquid electrolytes.The capacitance retention increases to 54.5％ from 28.5％ at 100 A/g (compare to 2 A/g) in H3PO4 and increases to 65.1％ from 46.3％ at 2 A/g (compare to 0.2 A/g) in neat ionic liquid.A high energy density of 84.4 Wh/kg is obtained within the voltage window of 4 V in ionic liquid.Even at a high-power density of 1000 W/kg,the VOx-bonded graphene shows a high energy density of 47.3 Wh/kg.