Highly Diluted Pt Atoms Modified RhBi Intermetallic Nanoplates Boost Ethanol Oxidation Electrocatalysis

Engineering Pt-based multimetallic nanoalloys could boost electrocatalysis in broad applications, yet it remains challenging in terms of its rational design and synthesis of a highly diluted alloy with unprecedented Pt atomic utilization. Herein, atomically dispersed Pt anchored on the surface of novel RhBi intermetallic nanoplates (RhBi-Pt_a) is achieved by atomic replacement, which transforms into a tensile-strained and highly diluted RhPt_a alloy (RhBi@RhPt_a) via electrochemical dealloying. Due to the diluted Pt atoms and tensile-strained Rh shell, the RhBi@RhPt_a electrocatalyst exhibits a remarkably enhanced peak mass activity of 32459.1 mA mg^-1_Pt toward the ethanol oxidation reaction (EOR) in alkaline electrolyte, while RhBi and RhBi-Pt_a intermetallic nanocrystals show negligible activities. This work provides a general strategy for engineering highly diluted alloys for highly efficient electrocatalysis, based on the well-defined intermetallic compounds. © 2025 American Chemical Society.