Janus MoSi₂P₂As₂ Decorated with Transition Metal Atoms as Efficient Bifunctional HER/OER and OER/ORR Electrocatalysts

Abstract

It is of great importance to develop bifunctional electrocatalysts with high efficiency and low cost for water splitting and fuel cells. Herein, based on the new emerging two-dimensional material of MoSi₂N₄, we explore the potentials of novel Janus MoSi₂P₂As₂ (labeled as MSPA) in electrocatalytic applications. We conduct a comprehensive study using first-principles calculations to explore the potential of Janus MoSi₂P₂As₂ decorated with 13 kinds of transition metal atoms as efficient bifunctional catalysts for the hydrogen/oxygen evolution reaction (HER/OER) and oxygen evolution/reduction reaction (OER/ORR). After screening, results show that Rh@MSPA and Au@MSPA can serve as bifunctional catalysts for OER/ORR with overpotentials of 0.27/0.29 V and 0.42/0.37 V, and Pt@MSPA exhibit great potential as HER/OER catalyst with an overpotential of -0.004/0.51 V. The solvation effect on catalytic activity is also investigated. The volcano diagrams are employed to depict the activity trends toward HER, OER, and ORR. The d-band center, ICOHP and intrinsic descriptor φ can serve as quantitative descriptors of ORR/OER activity and reveal the activity origin of OER/ORR. This study presents a viable approach for developing advanced electrocatalysts with multiple functionalities, thereby expanding the utilization of Janus MoSi₂P₂As₂ in electrocatalysis.