Spatiotemporal Engineering for the Synthesis of Multi‐Scale Turing‐Patterned High‐Entropy Alloys

ABSTRACT Subnanoscale alloys are recognized as innovative electrocatalysts for sustainable energy conversion systems. However, their confinement to a single‐scale framework often impedes their ability to meet the multifaceted demands of catalytic reactions. Here, we propose a spatiotemporal control strategy that leverages interfacial etching‐driven reaction‐diffusion, guided by a specific atomic self‐arrangement, for the versatile fabrication of multi‐scale Turing‐patterned alloys. These alloys, formed on three‐dimensional nanoporous metal compounds, feature sub‐2 nm stripe widths, compositions from binary to high‐entropy, and successfully overcome conventional limitations in stripe width and composition. The tunable cross‐scale structures of these materials facilitate efficient co‐production of hydrogen and benzonitrile at high current densities. This excellent performance, revealed by combined computational and experimental studies, originates from the synergy of defects, stress, and confinement effects in the Turing patterns, as well as optimal transport within the nanoporous framework. Our strategy provides a viable pathway for the cross‐scale manufacturing of functional alloys with diverse applications.