Polyoxometalate-based MOF derived Co2N/Co3W3C/coal-based carbon fibers self-supporting catalyst for efficient hydrogen evolution

The strategic design of effective and low-cost catalysts plays a crucial role in advancing hydrogen evolution reaction (HER) in electrocatalytic water splitting. The integration of non-precious metal catalysts through a cooperative bimetallic compound strategy is crucial as an alternative to conventional precious metal-based materials. Transition metal carbides (TMCs) and nitrides (TMNs) exhibit Pt-like electronic configurations, demonstrating high potential as electrode catalysts for HER. Herein, Co 2 N/Co 3 W 3 C/coal-based carbon fibers (Co 2 N/Co 3 W 3 C/C-CFs) was synthesized via electrospinning and pyrolysis processes with the presence of polyoxometalate-based metal–organic framework (POMOF) of PW 12 -ZIF-67 as a precursor, and urea as a nitrogen source. The small-sized PW 12 -ZIF-67 allowed a better match with the diameters of C-CFs. The synergistic interaction between Co 2 N and Co 3 W 3 C effectively modulated the electronic structure and facilitated rapid charge transfer, endowing the composite with exceptional HER activity. Additionally, the flexible C-CFs not only effectively prevented agglomeration of Co 2 N/Co 3 W 3 C nanoparticles but also acted as self-supporting electrode. Notably, the Co 2 N/Co 3 W 3 C/C-CFs composite exhibited outstanding HER activity, achieving an overpotential of 92 mV at a current density of 10 mA cm −2 in 0.5 M H 2 SO 4 . This study achieves the successful conversion of coal into high-performance carbon materials and provides a feasible strategy for developing efficient HER catalysts based on POMOF-derived non-precious metal compounds.