Indium-based bimetallic clusters anchored onto silicon-doped graphene as efficient multifunctional electrocatalysts for ORR, OER, and HER

Exploring efficient, economical, and environmentally friendly multifunctional electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is a pre-requisite for the development of renewable energy conversion and storage technologies. Herein, the catalytic performance of indium-based bimetallic clusters anchored onto silicon-doped graphene (In2M2/Si-G, M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) as multifunctional electrocatalysts is investigated systematically by density functional theory methods. All the studied In2M2 bimetallic clusters can be stably anchored onto the Si-G substrate based on the calculated binding energy. Among these materials, In2V2/Si-G and In2Co(2)/Si-G are expected to be potential trifunctional (ORR/OER/HER) electrocatalysts with the low overpotentials of 0.51/0.76/-0.11 V and 0.56/0.36/-0.09 V, respectively. Emphatically, the electronic structure analysis reveals that such high catalytic activity can be attributed to the synergistic effect between indium and transition metal atoms, which could effectively promote electron transfer between catalyst and reaction species. This work would open a new perspective and provide guidance for designing promising multifunctional electrocatalysts to meet energy demand.