Yan Song
Institute of Coal Chemistry, China
Title: Porous worm-like NiMoO4 coaxially decorated electrospun carbon nanofibers as binder-free high performance electrodes for supercapacitors and lithium-ion batteries
Biography
Biography: Yan Song
Abstract
Recently, various nanoscale NiMoO4 structures have been synthesized and evaluated as electrode materials in both SCs and LIBs due to the relatively low cost, abundant availability, environmental benignity and inherent electrochemical advantages. Given the NiMoO4 prepared in these works exhibits small surface area and dense structure, which impedes the fast ions transport and makes it difficult to alleviate the volume change. Therefore, it will be of great significance to grow porous NiMoO4 nanostructure directly on flexible substrates for effective energy storage. As another carbon textile, electrospun carbon nano fibers (ECNFs) exhibit smaller diameter and lighter mass when compared with conventional carbon cloth, which is favorable to increase the loading of NiMoO4, shorten ion/electron transport pathways and improve the utilization of NiMoO4. The peculiar architectures consisting of electrospun carbon nanofibers coaxially decorated by porous worm-like NiMoO4 were successfully fabricated for the first time to address the poor cycling stability and inferior rate capability of state-of-the-art NiMoO4-based electrodes. The porous worm-like structure endows the electrode high capacitance/capacity due to large specific surface area and short electron/ion diffusion channels. Moreover, the robust integrated electrodes with sufficient internal spaces can self- accommodate volume variance during charge/discharge processes, which is beneficial to the structural stability and integrity. By the virtue of rational design of the architecture, the hybrid electrode delivered high specific capacitance (1088.5 F g-1 at 1 A g-1), good rate capability (860.3 F g-1 at 20 A g-1) and long lifespan (73.9% capacitance retention after 5000 cycles at 10 A g-1) when applied as supercapacitor electrode. For lithium-ion battery application, the electrode exhibited a high reversible capacity of 689.7 mAh g-1 even after 150 continuous cycles at a current density of 1 A g-1.