Zhang Wang, Huo Xin, Li Xusen, Park Sumin, Lin Liwei, Park Sang Yoon, Diao Guowang, Piao Yuanzhe
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225009, Jiangsu, P. R. China.
Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Suwon-si 16229, Gyeonggi-do, Republic of Korea.
Langmuir. 2022 Aug 23;38(33):10331-10337. doi: 10.1021/acs.langmuir.2c01863. Epub 2022 Aug 15.
By introducing a heteroatom into carbon material, an effective improvement in capacitance can be realized owing to surface oxidation and reduction reactions of pseudocapacitors. Herein, a simple one-pot carbonization activation method was proposed to convert potassium citrate into three-dimensional interconnected porous carbon (PC). Then, an effective double heteroatom doping method by thiourea was used to prepare nitrogen-sulfur-doped PC (N,S-PC). This porous structure facilitates the storage of a large number of ions and reduces their diffusion path. The synthesized N,S-PC nanomaterial has a capacitance of 674 F/g at 1 A/g in a 1 M HSO electrolyte, can retain 94.41% of the initial capacitance after 10 000 cycles at 5 A/g, and has a long cycle life. More importantly, a symmetric supercapacitor assembled with this material can exhibit an energy density of up to 32.6 (W·h)/kg at a high-power density of 750 W/kg. This is due to the high performance of N,S-PC in supercapacitor electrode materials.
通过将杂原子引入碳材料中，由于赝电容器的表面氧化和还原反应，可以实现电容的有效提高。在此，提出了一种简单的一锅法碳化活化方法，将柠檬酸钾转化为三维互连多孔碳（PC）。然后，采用硫脲进行有效的双杂原子掺杂方法制备氮硫共掺杂PC（N,S-PC）。这种多孔结构有利于大量离子的存储并减少其扩散路径。合成的N,S-PC纳米材料在1 M HSO电解液中，1 A/g电流密度下的电容为674 F/g，在5 A/g电流密度下循环10000次后可保留初始电容的94.41%，具有长循环寿命。更重要的是，用这种材料组装的对称超级电容器在750 W/kg的高功率密度下可表现出高达32.6 (W·h)/kg的能量密度。这是由于N,S-PC在超级电容器电极材料中具有高性能。
