Enhanced Catalytic Performance of Vanadium-Doped MoS₂ as a Multifunctional Electrocatalyst toward ORR, OER, and HER Applications

The development of efficient and multifunctional electrocatalysts is crucial for advancing catalytic applications, including the oxygen reduction reaction (ORR), the oxygen evolution reaction (OER), and the hydrogen evolution reaction (HER). These three reactions are among the most crucial electrochemical processes, playing a central role in various energy conversion and storage systems, such as fuel cells, water electrolyzers, and metal–air batteries. In this work, we study the structural, electronic, and catalytic properties of vanadium(V)-doped monolayer MoS 2 (V-MoS 2 ) using density functional theory (DFT). Our findings show that V-MoS 2 exhibits considerably improved catalytic performance compared to pristine MoS 2 . V doping decreases the electronic band gap from 2.56 to 0 eV and transitions MoS 2 to a conducting phase capable of readily facilitating the transfer of electrons. Both ORR and OER analyses exhibit favorable chemical reaction pathways and lower Gibbs free energy changes, demonstrating high catalytic activity. In terms of the HER, V-MoS 2 shows near-optimal Gibbs free energy values for hydrogen adsorption, supporting its ability to efficiently provide hydrogen evolution catalysis. This study not only provides V-MoS 2 as a multifunctional electrocatalyst but also increases understanding of its operation from structure to function and realizes its usefulness in future development. The present research work provides an insight into the evolution of 2D TMD-based multifunctional electrocatalysts toward HER, ORR, and OER and also a deep understanding of the nature of active sites.