Unraveling the electrocatalytic properties of non-noble metal-based nickel-cobalt-tungsten/MXene heterocomposite towards trifunctional hydrogen evolution reaction, oxygen evolution reaction, and methanol oxidation reaction

This paper proposes NiCoW@Ti₃C₂ MXene composite as a non-noble metal-based catalyst, utilizing a strong metal-support interaction strategy through a facile one-step hydrothermal approach. Through physicochemical characterizations, the well-formed heterostructure is confirmed at NiCoW/Ti₃C₂ MXene interface. Notably, electrochemical evaluations reveal that NiCoW@Ti₃C₂ (20 wt%) electrocatalyst exhibits superior activity for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), exhibiting lower onset potentials for HER (0.107 and 0.222 V) and OER (0.244 and 0.328 V) at current densities of 100 and 300 mA/cm², surpassing values are reported by recent catalysts. The water-splitting device, utilizing the NiCoW@Ti₃C₂ (20 wt%) as a bifunctional electrode, achieves a lower voltage of 1.51 V to achieve a current density of 10 mA/cm². Density functional theory (DFT) calculations further elucidate the enhanced HER/OER activity of the hybrid NiCoW/Ti₃C₂ surface. Additionally, stability is assessed using time series analysis (TSA), which accurately predicts the experimental potential (E) trends, confirming TSA's applicability for modeling the cell's electrochemical behavior. Methanol oxidation reaction (MOR) activity is also extensively explored in alkaline media, demonstrating strong electrocatalytic performance due to the synergistic effects of Ni, Co, W, and 2D MXene. These findings position NiCoW/Ti₃C₂ as a promising multifunctional catalyst for sustainable energy conversion applications.