Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (6): 755-762.DOI: 10.6023/A21030087 Previous Articles     Next Articles



高润洲, 李国昌, 陈轶群, 曾誉, 赵杰, 吴强*(), 杨立军, 王喜章, 胡征   

  1. 南京大学化学化工学院 介观化学教育部重点实验室 南京 210023
  • 投稿日期:2021-03-11 发布日期:2021-05-18
  • 通讯作者: 吴强
  • 基金资助:
    国家自然科学基金(21972061); 国家自然科学基金(21832003); 国家自然科学基金(21773111); 中央高校基本科研业务费专项资金(14380237); 南京大学博士研究生创新研究项目(CXYJ21-38)

Carbon Nanocages//Tungsten Trioxide Nanorods Supercapacitors with in situ Polymerized Gel Electrolytes

Runzhou Gao, Guochang Li, Yiqun Chen, Yu Zeng, Jie Zhao, Qiang Wu(), Lijun Yang, Xizhang Wang, Zheng Hu   

  1. Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
  • Received:2021-03-11 Published:2021-05-18
  • Contact: Qiang Wu
  • Supported by:
    National Natural Science Foundation of China(21972061); National Natural Science Foundation of China(21832003); National Natural Science Foundation of China(21773111); Fundamental Research Funds for the Central Universities(14380237); Nanjing University Innovation Program for PhD candidate(CXYJ21-38)

Asymmetric supercapacitors can effectively increase the energy density of supercapacitors, and the key is to develop high-performance electrode materials and electrolytes. Hierarchical carbon nanocages are promising electrode materials for supercapacitors because of the large specific surface area, coexisting micro-meso-macropore, good conductivity and high stability. By introducing pseudocapacitance and improving wettability via N&S dual-doping, the N&S dual-doped carbon nancages (NSCNC) exhibit a high specific capacity of 337 F?g-1 at 1 A?g-1 within the potential window of 0~1 V in 1 mol?L-1 H2SO4solution. Hydrated tungsten trioxide (WO3?0.6H2O) nanorods can achieve the insertion/de-insertion of H+ via the redox reaction between W6+/W5+, and exhibit a high specific capacity of 454 F?g-1 at 5 A?g-1 within the potential window of –0.55~0.3 V. The solid-state asymmetric supercapacitor (SASC) with NSCNC and WO3?0.6H2O nanorods as positive and negative electrodes, and in situ polymerized gel electrolyte (IPGE/H2SO4) as solid electrolyte has the working voltage of 1.5 V. And the rate performance of the SASC is very close to that of the H-type device with 1 mol?L-1 H2SO4 solution as electrolyte, much better than the counterpart with the traditional gel electrolyte of polyvinyl alcohol/sulfuric acid (PVA/H2SO4). The much improved SASC performance is attributed to the establishment of the effective charge transfer interface between the IPGE/H2SO4 and the electrode materials, which enhances the transfer of H+ ions and thereby much reduces theIR drop. The energy density of the SASC with IPGE/H2SO4 is 22.31 Wh?kg-1 at 0.375 kW?kg-1 (0.5 A?g-1) and 8.55 Wh?kg-1 at 7.5 kW?kg-1 (10 A?g-1), locating at the top-ranking of literatures. The SASC also exbibits excellent cycling stability, with the capacity retention of 95.2% after 4000 cycles at 5 A?g-1. This study not only demonstrates the excellent energy storage performance of NSCNC//WO3?0.6H2O supercapacitors in acidic electrolytes, but also provides a new in-situ polymerized gel electrolyte for building high-performance SASCs.

Key words: supercapacitor, acidic electrolyte, in situ polymerized gel electrolyte, hierarchical carbon nanocage, hydrated tungsten trioxide nanorod