Computational screening for high-activity MoS2 monolayer-based catalysts for the oxygen reduction reaction via substitutional doping with transition metal

Abstract

Rational design of non-noble materials as highly efficient, economical, and durable platinum-free oxygen reduction reaction (ORR) electrocatalysts is crucial to the large-scale application of fuel cells. In this work, using density functional theory (DFT) computations, the catalytic activity for the ORR of substitutionally doped MoS₂ monolayers with various transition metal (TM) atoms was systemically explored. The computations reveal that these TM atoms can strongly interact with the S-vacancy and significantly modify the electronic and magnetic properties of MoS₂ monolayer. On the basis of the computed free energies, it is evident that Cu-embedded MoS₂ monolayer exhibits the best ORR catalytic activity with the minimum overpotential of 0.63 V because of its optimal interaction with ORR species. Thus, this study suggests that substituted doping with a suitable transition metal is an effective method to improve the catalytic activity of MoS₂ monolayer for the ORR, which could be useful in development of novel 2D ORR electrocatalysts.