Li Jun, Xia Zhenhai, Wang Xiaowei, Feng Cheng, Zhang Qingcheng, Chen Xi'an, Yang Yun, Wang Shun, Jin Huile
Key Lab of Advanced Energy Storage and Conversion, Zhejiang Province Key Lab of Leather Engineering, College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang, 325035, China.
Zhejiang Engineering Research Center for Electrochemical Energy Materials and Devices, Institute of New Materials and Industrial Technologies, Wenzhou University, Wenzhou, Zhejiang, 325035, China.
Adv Mater. 2024 Mar;36(13):e2310422. doi: 10.1002/adma.202310422. Epub 2023 Dec 24.
The acidic aqueous supercapacitors have been found to deliver appealing capacitive properties due to fast ion diffusion caused by the applied smallest size of hydrion. However, their practical applications are largely inhibited by the narrow electrochemical stability window of water (1.23 V). Herein, A nitrogen-enriched porous carbon materials (RNOPCs) is reported, consisting of varied nitrogen doping bonded on sp and sp carbon sites, which are capable of stimulating a wider potential window up to 1.4 V and thus resulting in a great enhancement of capacitive performance in aqueous acidic electrolytes. Together with the improved electrical conductivity and preferable hydrion diffusion, RNOPCs exhibit an ultrahigh volumetric capacitance (1084 F cm) in 0.5 M HSO. Besides, a fully packed RNOPCs-based symmetrical supercapacitor can deliver a high gravimetric and volumetric energy density of 31.8 Wh Kg and 54.3 Wh L respectively, approaching those of lead acid batteries (25-35 Wh Kg). The first-principles calculations reveal that the lone pair electrons of the doped nitrogen can be delocalized on its neighboring carbon atoms, improving charge uptakes and overpotentials. Such facile and scale-up production of carbon-based supercapacitors can bridge the gap of energy density between traditional supercapacitors and batteries in aqueous electrolytes.
由于所施加的最小尺寸氢离子导致离子快速扩散，酸性水系超级电容器已被发现具有吸引人的电容特性。然而，水的窄电化学稳定性窗口（1.23V）在很大程度上限制了它们的实际应用。在此，报道了一种富氮多孔碳材料（RNOPCs），它由键合在sp和sp碳位点上的不同氮掺杂组成，能够激发高达1.4V的更宽电位窗口，从而在水性酸性电解质中极大地提高电容性能。连同改善的电导率和较好的氢离子扩散，RNOPCs在0.5M HSO中表现出超高的体积电容（1084F cm）。此外，一个完全组装的基于RNOPCs的对称超级电容器分别可以提供31.8Wh Kg和54.3Wh L的高比能量和体积能量密度，接近铅酸电池（25 - 35Wh Kg）的水平。第一性原理计算表明，掺杂氮的孤对电子可以在其相邻碳原子上离域，改善电荷吸收和过电位。这种基于碳的超级电容器的简便且可扩大规模的生产可以弥合水性电解质中传统超级电容器和电池之间的能量密度差距。
