Boosting hydrogen oxidation performance of bimetallic telluride by electrochemical surface engineering

Electrochemically induced surface reconstruction offers a novel approach for in situ modulation of the surface structure of nanomaterials. However, comprehensive studies on the surface reconstruction behavior of nanomaterials under diverse electrochemical operations remain limited. Here, exemplified by three electrochemical operations, including cyclic voltammetry (CV), square‐wave potential (SWP) and chronoamperometry (CA), we reveal the structural evolution behavior and the corresponding electrocatalytic activity of bimetallic telluride hollow nanorods (Ir 1‐ x Ru x Te 2 HNRs). It was found that the surface Te atoms in Ir 1‐ x Ru x Te 2 HNRs undergo preferential leaching during the CV and SWP processes, ultimately leading to the formation of a metal alloy shell. In contrast, during the CA process, the surface reconstruction induced by Te leaching was suppressed by the adsorption of anions on the electrode surface. Electrocatalytic tests show that the CV activated Ir 0.75 Ru 0.25 Te 2 HNRs exhibit excellent activity for the hydrogen oxidation reaction in 0.1 M KOH, with a mass activity of 686 A g −1 at an overpotential of 50 mV, which is 2.9 times higher than that of commercial Pt/C catalyst. Density functional theory (DFT) computation reveals that the incorporation of Ru optimizes the hydroxyl binding energy of IrRu alloy, thus resulting in the reduced reaction energy barrier of hydrogen oxidation reaction. This work provides a new insight into the design of efficient catalysts through electrochemical surface engineering.