Wang Tianhao, Zhang Wentao, Yang Shujuan, Liu Xuejiao, Zhang Liping
Beijing Key Laboratory of Lignocellulosic Chemistry, MOE Engineering Research Center of Forestry Biomass Materials and Bioenergy, Beijing Forestry University, No. 35 Tsinghua East Road, Haidian District, Beijing 100083, P. R. China.
ACS Omega. 2020 Mar 5;5(10):4778-4786. doi: 10.1021/acsomega.9b03006. eCollection 2020 Mar 17.
Unusual polypyrrole/graphene/cellulose nanofibril (PPy/GR/CNF) composite particles were fabricated by introducing an in situ oxidative polymerization approach. Structural characterization of the composite particles showed foam-like network morphology with a large surface area of 621 m/g. The PPy/GR/CNF sample exhibited remarkable capacitance behavior in 1 M NaSO. It showed a high specific capacitance of 264.3 F/g at 0.25 A/g, which represents a 51.7% increase compared to that of PPy/GR and a high capacitance of 155.5 F/g even at a high current density of 5 A/g. Meanwhile, it possessed high rate capability and good cycling performance (85.7% capacitance retention even after 1000 cycles). These excellent electrochemical performances were attributed to the structure of PPy/GR/CNF that can provide large surface areas and shorten electron diffusion pathways. More importantly, the CNF stabilized the structure of PPy and prevented chain breakdown during the charge/discharge process, which improved the cycling performance. Hence, this PPy/GR/CNF composite shows great potential for the fabrication of high-capacitance and low-cost supercapacitor electrode materials with good cycling performance.
通过引入原位氧化聚合法制备了不同寻常的聚吡咯/石墨烯/纤维素纳米纤维（PPy/GR/CNF）复合颗粒。复合颗粒的结构表征显示出具有621 m²/g大表面积的泡沫状网络形态。PPy/GR/CNF样品在1 M Na₂SO₄中表现出显著的电容行为。在0.25 A/g时，它显示出264.3 F/g的高比电容，与PPy/GR相比增加了51.7%，即使在5 A/g的高电流密度下也具有155.5 F/g的高电容。同时，它具有高倍率性能和良好的循环性能（即使在1000次循环后电容保持率仍为85.7%）。这些优异的电化学性能归因于PPy/GR/CNF的结构，该结构可以提供大表面积并缩短电子扩散路径。更重要的是，CNF稳定了PPy的结构并防止了在充放电过程中的链断裂，从而提高了循环性能。因此，这种PPy/GR/CNF复合材料在制备具有良好循环性能的高电容和低成本超级电容器电极材料方面显示出巨大潜力。
