Bifunctional molybdenum carbide based hybrids for electrocatalytic water splitting

For electrochemical water splitting, the fabrication and designing of an active, robust, and stable bifunctional catalyst is the most challenging issue. In this work we report the electrocatalytic ability hybrid of Molybdenum Carbide (Mo₂C) and ZIF-67 hybrid heterostructures fabricated by annealing at high temperatures. This bifunctional electrocatalyst have shown an outstanding performance for water splitting with high activity both for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) processes. The hybrid (MCZ-2) with ratio of 1:2 have shown superior catalytic activity with a low overpotential of 169 mV and 208 mV at the current density of 10 mA/cm² and 20 mA/cm² respectively for HER. Similarly, for OER, it shows overpotential of 340 mV and 370 mV at the current density of 20 mA/cm² and 50 mA/cm². Besides, the MCZ-2 have shown a long-term stability 24 h at the current density of 100 μA/cm². The boosted HER and OER activity of the hybrid is attributed to synergetic effect between ZIF-67 and Mo₂C and modulation of active sites due to the presence of N and Co in the hybrid.