Super long-life supercapacitor electrode materials based on hierarchical porous hollow carbon microcapsules

作者：Ran, Fen^*; Zhang, Xuanxuan; Liu, Yuansen; Shen, Kuiwen; Niu, Xiaoqin; Tan, Yongtao; Kong, Lingbin; Kang, Long; Xu, Changan; Chen, Shaowei

来源：RSC Advances, 2015, 5(106): 87077-87083.

DOI：10.1039/c5ra15594k

• ELECTROCHEMICAL PERFORMANCE
• GRAPHENE NANOSHEETS
• NANOTUBES
• POLYANILINE
• FABRICATION
• PYROLYSIS
• POROSITY

Remarkable supercapacitor electrodes with a high specific supercapacitance and a super long cycle life were achieved by using hierarchical porous hollow carbon microcapsules (HPHCMs) as active materials. HPHCMs were prepared by a facile chemical route based on pyrolysis of a soft sacrificial template involving a non-crosslinked core of poly(styrene-r-methylacrylic acid) and a crosslinked shell of poly(styrene-r-divinylbenzene-r-methylacrylic acid), which were synthesized by using traditional radical polymerization and emulsion polymerization. The results of scanning electron microscopy, transmission electron microscopy and Brunauer-Emmett-Teller characterizations revealed that HPHCM possessed the desired pore structure with apparent macro-/meso- and micropores, which not only provided a continuous electron-transfer pathway to ensure good electrical contact, but also facilitated ion transport by shortening diffusion pathways. As electrode materials for supercapacitor, a high specific capacitance of 278.0 F g(-1) was obtained at the current density of 5 mA cm(-2). Importantly, after 5000 potential cycles in 2 M KOH electrolyte at the discharge current density of 20 mA cm(-2), the capacitance actually increased from 125 to 160 F g(-1) and then remained 151 F g(-1), corresponding to a capacitance retention of 120%, likely due to electrochemical self-activation.

• 出版日期2015
• 单位兰州理工大学; 国家海洋局第三海洋研究所