Tuning the crystal structure of NiS/carbon by Mo doping for asymmetric supercapacitor application. (December 2022)

• Record Type: Journal Article
• Authors: Qu, Y.; Sun, L.; Xie, F.; Hu, J.; Tan, H.; Qian, J.; Shi, X.; Zhang, Y.
• Is Part Of: Materials today chemistry. Volume 26(2022)
• Publication Date: 2022-12
• Subjects: Ni-sulfide -- Carbon -- Density functional theory -- Microstructure; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2022.101188
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: A major challenge faced by NiS as positive electrode material for supercapacitors is the capacity attenuation caused by structural changes in the charging and discharging process. In this article, based on theoretical calculations and experimental studies, it is demonstrated that Mo doping can significantly improve the stability and specific capacitance of NiS for supercapacitor application. Experiments show that compared with original NiS/C, the cycle stability of the doped Mo-NiS/C increases by about 30% after 5, 000 cycles, and the specific capacitance achieves 1, 852 F/g at 1 A/g. Besides, Mo doping can bring better ion contact and increased reaction site to the original lamellar structure of NiS. The calculation results also show that the bond energy of the doped Mo-NiS/C is lower than that of the original NiS/C, which hinders the structural transformation or other side reactions and achieves a better cycle life. This article verifies the effect of Mo doping on the properties of NiS/C and provides a feasible scheme for the study of metal-doped sulfide. Highlights: Theoretical calculation prediction of the effect of Mo doping in increasing conductivity and reducing ion adsorption energy. Simple synthesis method including hydrothermal reaction, carbonization, and vulcanization. Favorable lamellar structure of Mo-NiS/C with large specific surface area and internal voids. Higher specific capacitance, larger initial capacity retention, and better rate performance of doped Mo-NiS/C than NiS/C.