Phosphide-oxide honeycomb-like heterostructure CoP@CoMoO₄/CC for enhanced hydrogen evolution reaction in alkaline solution

The design and construction of effective and stable hydrogen evolution reaction (HER) catalysts represent the key to obtaining hydrogen energy economically. Transition metal phosphides (TMPs) have attracted considerable attention due to their unique catalytic mechanism, which is similar to hydrogenase. However, single-phase TMPs remain limited by their low activity and weak stability in alkaline solutions. In this work, CoP@CoMoO₄ nanosheets with phosphide and oxide heterostructure were synthesized on carbon cloth (CC) through hydrothermal method and subsequently reacted with red phosphorus in a tube furnace. The outstanding synergy between CoP and CoMoO₄ enhanced the HER activity and stability in alkaline solution. The CoP@CoMoO₄/CC heterostructure exhibited excellent HER activity with a low overpotential of 89 mV at 10 mA cm⁻² with Tafel slope of 69 mV dec^-1, and outstanding stability when compared with single-phase phosphides. Our present research provides a new approach for the preparation of inexpensive, highly active, and highly durable phosphorus-based catalyst for HER.