Liu Huichao, Zhu Sheng, Zhang Yu, Song Hua, Zhang Ying, Chang Yunzhen, Hou Wenjing, Han Gaoyi
Institute of Molecular Science, Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province, Key Laboratory of Chemical Biology and Molecular Engineering of Education Ministry, Shanxi University, Taiyuan, 030006, P. R. China.
College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
Small. 2023 Oct;19(40):e2204119. doi: 10.1002/smll.202204119. Epub 2023 May 31.
Heteroatom-doped porous carbon materials with distinctive surface properties and capacitive behavior have been accepted as promising candidates for supercapacitor electrodes. Currently, the researches mainly focus on developing facile synthetic method and unveiling the structure-activity relationship to further elevate their capacitive performance. Here, the B, N co-doped porous carbon sheet (BN-PCS) is constructed by one-pot pyrolysis of agar in KCl/KHCO molten salt system. In this process, the urea acts as directing agent to guide the formation of 2D sheet morphology, and the decomposition of KHCO and boric acid creates rich micro- and mesopores in the carbon framework. The specific capacitance of optimized BN-PCS reaches 361.1 F g at a current density of 0.5 A g in an aqueous KOH electrolyte. Impressively, the fabricated symmetrical supercapacitor affords a maximum energy density of 43.5 Wh kg at the power density of 375.0 W kg in 1.0 mol L TEABF /AN electrolyte. It also achieves excellent long-term stability with capacitance retention of 91.1% and Columbic efficiency of 100% over 10 000 cycles. This study indicates one-pot molten salt method is effective in engineering advanced carbon materials for high-performance energy storage devices.
具有独特表面性质和电容行为的杂原子掺杂多孔碳材料已被公认为超级电容器电极的有前途的候选材料。目前，研究主要集中在开发简便的合成方法和揭示结构-活性关系，以进一步提高其电容性能。在此，通过在KCl/KHCO熔盐体系中对琼脂进行一锅热解制备了B、N共掺杂多孔碳片（BN-PCS）。在此过程中，尿素作为导向剂引导二维片状形态的形成，KHCO和硼酸的分解在碳骨架中产生丰富的微孔和介孔。在水性KOH电解质中，优化后的BN-PCS在电流密度为0.5 A g时的比电容达到361.1 F g。令人印象深刻的是，在1.0 mol L TEABF/AN电解质中，所制备的对称超级电容器在功率密度为375.0 W kg时提供了43.5 Wh kg的最大能量密度。它还具有出色的长期稳定性，在10000次循环中电容保持率为91.1%，库仑效率为100%。这项研究表明一锅熔盐法在制备用于高性能储能器件的先进碳材料方面是有效的。
