Charge-redistributed RuNi/MoN heterojunction enables efficient hydrogen evolution in a wide pH range.

Electrocatalytic hydrogen production offers a promising solution to address current energy depletion. Herein, a RuNi/MoN heterostructure on carbon cloth (CC), RuNi/MoN@CC, was successfully constructed using a simple method, allowing for dual regulation of morphology and electronic structure. Under the influence of Ni, the in-situ generated MoN inherits the morphology of the NiMoO₄ precursor, presenting a nanowire morphology, which is favorable for increasing electrochemical active area. Otherwise, the introduction of Ni acts as a sacrificial reducing agent and ensures that Ru remains in zero oxidation state as an electron donor to optimize the internal electronic distribution. Under the influence of dual regulation, the RuNi/MoN@CC requires only 66, 92, and 149 mV to achieve a current density of -10 mA cm^-2 in alkaline, neutral, and acidic electrolytes, with the Tafel slopes of 50.4, 56.2, and 71.8 mV dec^-1. This work will provide effective guidance for future exploration of transition metal-based catalysts suitable for a wide pH range.