Liu Yuhao, Qu Xiaoxiao, Huang Guangxu, Xing Baolin, Zhang Fengmei, Li Binbin, Zhang Chuanxiang, Cao Yijun
College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454000, China.
Henan Key Laboratory of Coal Green Conversion, Henan Polytechnic University, Jiaozuo 454000, China.
Nanomaterials (Basel). 2020 Apr 23;10(4):808. doi: 10.3390/nano10040808.
Three-dimensional porous carbon is considered as an ideal electrode material for supercapacitors (SCs) applications owing to its good conductivity, developed pore structure, and excellent connectivity. Herein, using longan shell as precursor, 3-dimensional porous carbon with abundant and interconnected pores and moderate heteroatoms were obtained via simple carbonization and potassium hydroxide (KOH) activation treatment. The electrochemical performances of obtained 3-dimensional porous carbon were investigated as electrode materials in symmetric SCs with aqueous and solid electrolytes. The optimized material that is named after longan shell 3-dimensional porous carbon 800 (LSPC800) possesses high porosity (1.644 cm g) and N content (1.14 at %). In the three-electrode measurement, the LSPC800 displays an excellent capacitance value of 359 F g. Besides, the LSPC800 also achieves splendid specific capacitance (254 F g) in the two electrode system, while the fabricated SC employing 1 M LiSO as electrolyte acquires ultrahigh power density (15930.38 W kg). Most importantly, LSPC800 electrodes are further applied into the SC adopting the KOH/polyvinyl alcohol (PVA) gel electrolyte, which reaches up to an outstanding capacitance of 313 F g at 0.5 A g. In addition, for the all-solid-state SC, its rate capability at 50 A g is 72.73% and retention at the 10,000th run is 93.64%. Evidently, this work is of great significance to the simple fabrication of 3-dimensional porous carbon and further opens up a way of improving the value-added utilization of biomass materials, as well as proving that the biomass porous carbons have immense potential for high-performance SCs application.
三维多孔碳因其良好的导电性、发达的孔隙结构和优异的连通性，被认为是超级电容器（SCs）应用的理想电极材料。在此，以龙眼壳为前驱体，通过简单的碳化和氢氧化钾（KOH）活化处理，获得了具有丰富且相互连通的孔隙以及适量杂原子的三维多孔碳。研究了所得三维多孔碳作为电极材料在具有水性和固体电解质的对称SCs中的电化学性能。优化后的材料命名为龙眼壳三维多孔碳800（LSPC800），具有高孔隙率（1.644 cm³ g⁻¹）和氮含量（1.14 at%）。在三电极测量中，LSPC800显示出359 F g⁻¹ 的优异电容值。此外，LSPC800在两电极系统中也实现了出色的比电容（254 F g⁻¹），而采用1 M Li₂SO₄作为电解质制备的SCs获得了超高功率密度（15930.38 W kg⁻¹）。最重要的是，LSPC800电极进一步应用于采用KOH/聚乙烯醇（PVA）凝胶电解质的SCs中，并在0.5 A g⁻¹时达到了313 F g⁻¹ 的出色电容。此外，对于全固态SCs，其在50 A g⁻¹时的倍率性能为72.73%，在第10000次循环时的保持率为93.64%。显然这项工作对于三维多孔碳的简单制备具有重要意义，并进一步开辟了提高生物质材料高附加值利用途径同时证明生物质多孔碳在高性能SCs应用方面具有巨大潜力。
