Electrospinning derivative fabrication of sandwich-structured CNF/Co3S4/MoS2 as self-supported electrodes to accelerate electron transport in HER

The substitution of noble metal catalysts with earth abundant TMs as electrocatalysts for hydrogen production is of great significance. One biggest bottleneck for high-efficiency water electrolysis in TM catalysts is the sluggish reaction kinetics or electron transport efficiency. The electrical coupling between the substrate and the catalytic material can accelerate the electron transport, enhancing the charge transfer kinetics, and thereby improve the catalytic performance of the catalyst. Herein, we report a sandwich-structured CNF/Co3S4/MoS2, MoS2 grown in-situ on N-doped nanofibers with Co3S4 nanoparticles via electrospinning, carbonization and hydrothermal process, as self-supported electrodes for hydrogen evolution reaction. The sandwich structure is comprised of CNFs/Co3S4/MoS2 as substrate/accelerator/catalyst. Thereinto, the three-dimensional CNF framework, intrinsically doped by nitrogen, can open accessible channels for reactants and served as substrates for the in-situ growth of Co3S4 and MoS2 nanocrystals with high conductivity and massive active sites. Hence, the CNF/Co3S4/MoS2 shows outstanding catalytical performance in water electrospinning, only 80 mV required to drive 10 mA cm−2 current density with the Tafel slope of 99.2 mV dec−1 in alkaline media. Besides, the performance can be maintained for at least 40 h with negligible decline. This experiment can provide a new idea for the design of efficient and stable self-supporting electrodes.