Mesoporous Hexametallic High‐Entropy Alloy Nanotubes With Multicomponent Electronic Modulation for Efficient Bifunctional Catalysis
Abstract
Platinum‐based electrocatalysts are fundamentally constrained by strong oxygen binding, which restricts the oxygen reduction reaction (ORR) kinetics, and by severe CO poisoning, which hinders the methanol oxidation reaction (MOR). To address these limitations, we synthesized PdPtRuIrRhNi high‐entropy alloy (HEA) mesoporous nanotubes that enable cooperative multicomponent electronic interactions and lattice‐strain‐induced modulation of surface electronic structures. The resulting HEA nanotubes exhibited exceptional bifunctional performance, achieving an ultrahigh ORR mass activity of 4.04 A mg Pt −1 (16.8 times that of Pt/C) and a superior MOR mass activity of 3.19 A mg Pt −1 , alongside impressive stability (exemplified by a 92% ORR activity retention after 50,000 cycles). Mechanistic investigations, supported by density functional theory calculations and in situ Fourier‐transform infrared spectroscopy, revealed the electronic origin of this enhancement: multicomponent electronic interactions and lattice strain collectively induce a substantial downshift of the Pt d‐band center. This specific electronic modulation fundamentally reshapes the reaction pathways, shifting the rate‐determining step of the ORR from *O hydrogenation to *OH desorption and suppressing *CO accumulation in the MOR for a poisoning‐tolerant mechanism. Overall, these high‐entropy electrocatalysts driven by lattice strain and electronic redistribution represent a robust design principle for optimizing adsorption energetics and overcoming conventional kinetic limitations.