Bimetallic MOF derived Cu3P/Co2P grown on coal-based carbon fibers as self-supporting electrocatalyst for enhanced hydrogen evolution

Transition metal phosphides (TMPs) are often considered as a cost-effective replacement for precious metal catalysts in hydrogen evolution reaction (HER). Herein, the fibers are produced by combining coal with electrospinning technology, and then undergoing a pre-oxidation process for transforming into pre-oxidized coal-based fibers. Subsequently, CuCo-metal organic framework (CuCo-MOF) is grown on the pre-oxidized coal-based fibers using solvothermal method, and the Cu 3 P/Co 2 P/coal-based carbon fibers (Cu 3 P/Co 2 P/C-CFs) composite catalyst is successfully fabricated by phosphating at low temperature and carbonizing at high temperature. The uniformly grown nanoparticles (NPs) on the surface of C-CFs enhance the electrochemically active area, while the electron transfer between Cu 3 P and Co 2 P effectively modulates the electronic structure, increasing the catalytic activity of the catalyst for HER. In addition, the flexible C-CFs not only serve as self-supporting electrode but also effectively inhibit the agglomeration of Cu 3 P/Co 2 P NPs. Remarkably, the overpotential of Cu 3 P/Co 2 P/C-CFs is 83 mV at 10 mA cm −2 current density for HER in 0.5 mol L −1 H 2 SO 4 solution. This study presents promising strategies for the high value-added utilization of coal and the synthesis of highly effective non-precious metal catalysts.