High-performance 2.5 V aqueous asymmetric supercapacitor based on MnO2 nanowire/hierarchical porous carbon composite

作者：Li, Liangshuo; Pang, Shuhua^*; Fan, Xin^*; Wang, Yanfang; Cheng, Hua^*; Fang, Dong; Qin, Lin; Deng, Ming; Lu, Zhouguang

来源：MATERIALS TECHNOLOGY, 2022, 37(8): 780-788.

DOI：10.1080/10667857.2021.1879539

• Aqueous
• asymmetric supercapacitor
• high-performance
• porous carbon frameworks

Aqueous supercapacitor shows a narrow operating voltage range because of the limitation of the water electrolysis, resulting in low energy density. In this work, a nanoporous MnO2 entangled hierarchical porous carbon skeleton (simplified to MHPC) has been successfully prepared. Aqueous asymmetric supercapacitor has been assembled by employing the MHPC as a positive electrode, a hierarchical porous carbon skeleton (HPC) as a negative electrode, and a neutral Na2SO4 aqueous solution as electrolyte. The assembled asymmetric supercapacitor can be stably charged in an aqueous medium in a wide voltage range of 0-2.5 V and delivers a maximum energy density of 20.8Wh/kg at a power density of 0.25 kW/kg and 25 kW/kg at an energy density of 11.1 Wh/kg in a 1 M Na2SO4 aqueous solution. This strategy provides a new idea for developing high-energy supercapacitor.

• 单位
  桂林理工大学