Toward Rational Design of Catalysts Supported on a Topological Insulator Substrate

Abstract

Exotic and robust metallic surface states of topological insulators (TIs) have been expected to provide a promising platform for novel surface chemistry and catalysis. However, it is still not fully known how TIs affect the activity of catalysts. In this work, we study the effects of topological surface states (TSSs) on the activity of transition metal clusters (Au, Ag, Cu, Pt, and Pd), which are supported on a TI Bi2Se3 substrate. It was found the adsorption energy of oxygen on the supported catalysts can be always enhanced due to the TSSs. However, it does not necessarily mean an increase of the activity in catalytic oxidation reaction. Rather, the enhanced adsorption behavior in the presence of TSSs exhibits dual effects, determined by the intrinsic reactivity of these catalysts with oxygen. For the Au case, the activity of catalytic oxidation can be improved because the TSSs can enhance the dissociation rate of dioxygen. In contrast, a negative effect is found for the Pt and Pd clusters since the TSSs...