Transition Metal- Metal Carbide decorated N-Doped Carbon Framework as Efficient Dual Mott-Schottky Electrocatalysts for Water Splitting

Transition metal carbides (TMCs) have garnered significant attention as effective electrocatalysts for the hydrogen evolution reaction (HER), offering a highly active and stable alternative to precious metals like platinum, because of their d-band electronic structure resembling that of platinum. In this study, we address the challenge of developing a top-tier bifunctional electrocatalyst for efficient water splitting by employing a dual transition metal approach to electronically modify bimetallic carbides. Here, we have designed a composite structure through an in-situ fabrication process, featuring N-doped carbon nanotubes (CNT) and graphene, which serve as anchors for Co/MoC, Co/WC, and Co/VC. This integrated pyrolysis technique promotes synergistic interactions among these components and creates dual Mott-Schottky junctions, resulting in a bifunctional catalyst capable of catalyzing both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) with exceptional activity in both acidic and basic environments. Furthermore, it demonstrates excellent performance in water splitting under basic conditions, requiring a relatively low cell voltage of approximately 1.686 V to generate a current of 10 mA/cm2 while maintaining good stability. This superior performance is attributed to the cooperative electron transfer between the Co and MoC moieties and the defects induced by nitrogen doping in the graphene/CNT-based conductive network, distinguishing it from other recently reported Mo-based carbide materials.