Synthesis, formation mechanism and supercapacitor performance of MoS2/Mo2C/C nanofibers

Molybdenum Disulfide (MoS₂)-based nanostructures are mostly studied materials as an electrode for electrochemical energy storage devices, in particular supercapacitors, because of their innate electrochemical characteristics. However, the commercialization of the MoS₂-based electrodes is still bottlenecked. The engineered design of the material and their ternary hybrid structures are hoping to enhance their performance. In this work, we explain the process of in-situ formation of MoS₂/Mo₂C/C nanofibers, obtained through electrospinning followed by post-treatment and carbonization. The physical and chemical properties of the materials are thoroughly investigated using Raman Spectroscopy, FESEM, TEM and XRD. MoS₂/Mo₂C/C nanofiber hybrid exhibits a high specific (C_sp) capacitance of 940 F g⁻¹ at 1 A g⁻¹, surpassing that of the MoS₂ nanofibers (425 F g⁻¹) and carbon nanofiber (33 F g⁻¹). The capacitive retention obtained for MoS₂/Mo₂C/C and MoS₂ nanofiber is 82% and 62% up to 5000 cycles. This in situ formation method provides an idea for improving the electrochemical performance of MoS₂ nanofiber for further application of supercapacitor.