ABSTRACT The global demand for hydrogen (H2) production via electrolysis is rapidly increasing, necessitating the development of low‐cost and high‐performance electrocatalysts. Herein, we report the synthesis of a double‐transition‐metal (DTM) MXene, molybdenum titanium carbide (Mo2Ti2C3Tx), using a non‐hydrofluoric (HF) acid‐based etchant, followed by the incorporation of cobalt sulfide (CoS2) nanoparticles through a hydrothermal process. The optimized Mo2Ti2C3Tx@CoS2 composite demonstrated excellent electrocatalytic activity for the hydrogen evolution reaction (HER) in alkaline media, achieving a low overpotential of 281 mV at 10 mA/cm2, a Tafel slope of 79 mV/dec, and a high electrochemical active surface area (ECSA) of 375 cm2. Theoretical calculations further validated the efficiency of the material, and its application in a real‐time anion exchange membrane (AEM) electrolyzer confirmed its stability and high H2 production rate. These findings highlight Mo2Ti2C3Tx@CoS2 as a promising noble‐metal‐free electrocatalyst for sustainable H2 production and electrochemical energy conversion.
Hanan et al. (2026) studied this question.