posted on 2024-10-31, 06:29authored byShibo Wu, Ruiyang Hu, Yang Zhou, Jiahao He, Jingrui Cao, Muslum Demir, Pianpian Ma
The
advancement of negative electrode materials is essential for
enhancing the performance of supercapacitors. Fe–Mo-based bimetallic
carbide presents significant potential as a supercapacitor negative
electrode material. In this study, Fe3Mo3C/Mo2C composite nanofiber was synthesized using the electrospinning
method followed by high-temperature carbonization. As-prepared composite
nanofibers consist of two phases: Mo2C nanoparticles embedded
within the nanofiber and a block-like dispersion of the Fe3Mo3C phase. The Mo2C-dominated Mo2C/Fe3Mo3C-900 electrode shows an optimal specific
capacitance of 354.9 F g–1 at 1 A g–1, notably exceeding that of the Fe3Mo3C-dominated
Fe3Mo3C/Mo2C-900 electrode (253.2
F g–1). This advancement can be ascribed to the
enhanced textural characteristics and lower resistance. The assembled
NiCo2O4//Mo2C/Fe3Mo3C-900 device yields an energy density of 54.6 Wh kg–1 when the power density is 850 W kg–1. On the other
hand, the NiCo2O4//Mo2C/Fe3Mo3C-900 ASC device retained 67% of its capacitance after
5000 charge–discharge cycles, underperforming that of the NiCo2O4//Fe3Mo3C/Mo2C-900 (78%). This suggests that composite nanofiber with Mo2C as the main phase exhibits superior specific capacitance, while
the bimetallic carbide Fe3Mo3C presents higher
conductivity, which further improves its electrochemical stability.
In short, the as-designed Fe3Mo3C/Mo2C composite nanofibers present promising negative electrode features
for energy storage applications.