A Tensile-Strained Pt-Rh Single-Atom Alloy Remarkably Boosts Ethanol Oxidation.

Abstract

The rational design and control of electrocatalysts at single-atomic sites could enable unprecedented atomic utilization and catalytic properties, yet it remains challenging in multimetallic alloys. Herein, the first example of isolated Rh atoms on ordered PtBi nanoplates (PtBi-Rh₁ ) by atomic galvanic replacement, and their subsequent transformation into a tensile-strained Pt-Rh single-atom alloy (PtBi@PtRh₁ ) via electrochemical dealloying are presented. Benefiting from the Rh₁ -tailored Pt (110) surface with tensile strain, the PtBi@PtRh₁ nanoplates exhibit record-high and all-round superior electrocatalytic performance including activity, selectivity, stability, and anti-poisoning ability toward ethanol oxidation in alkaline electrolytes. Density functional theory calculations reveal the synergism between effective Rh₁ and tensile strain in boosting the adsorption of ethanol and key surface intermediates and the CC bond cleavage of the intermediates. The facile synthesis of the tensile-strained single-atom alloy provides a novel strategy to construct model nanostructures, accelerating the development of highly efficient electrocatalysts.