Two dimensional LiMgAs: A topological quantum catalyst for hydrogen evolution reaction

Abstract

Quantum materials, such as topological insulators (TIs), are promising due to diverse applications of their robust surface/edge states in the bulk three-dimensional (3D) and two-dimensional (2D) regimes. Such conducting surface states in 3D systems host “electron baths,” which are known to facilitate catalysis. However, the analogous effects in 2D scenarios wherein conducting helical edge states leading to Fermionic accumulation have been scarcely addressed. Using first-principles calculations, we demonstrate that the conducting edge states in 2D TIs, such as LiMgAs, can be exploited to facilitate excellent catalytic response toward hydrogen evolution reactions. The Gibbs free energy in such cases was found to be as low as −0.02 eV, which is quite superior compared to other materials reported in the literature. The concept presented herein can be extended to other well-known 2D TIs and used to realize unconventional topological quantum catalysts for ultra-high performance and efficient catalytic applications.