Yu, LiLiYuKao, Jui‐ChengJui‐ChengKaoZhang, YuefengYuefengZhangMak, Chun HongChun HongMakLo, Yu‐ChiehYu‐ChiehLoPao, Chun‐WeiChun‐WeiPaoJYH PIN CHOUWang, ZhenbinZhenbinWangChan, Ting‐ShanTing‐ShanChanHAO MING CHENHsu, Hsien‐YiHsien‐YiHsu2026-03-232026-03-232026-03-0909359648https://www.scopus.com/record/display.uri?eid=2-s2.0-105032408159&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/736517Achieving dynamic stability in single-atom catalysts (SACs) is challenging, as it requires balancing strong metal-support interactions with structural adaptability by incorporating flexibility into typically rigid SAC frameworks. Halide perovskites offer a unique platform for this purpose due to their soft ionic lattice and reversible dissolution–precipitation chemistry. We propose a concept for adaptively stabilizing SACs on halide perovskites through the integration of dynamic host chemistry, bandgap engineering, and light-regulated metal speciation. A light-induced bandgap funneling effect guides photogenerated carriers to deposit atomic platinum under illumination, while the dynamic interface prevents premature clustering during dark periods by refreshing the catalytic surface. The ionic, electronic, and atomic structural synergy enables a programmable intermittent illumination strategy, which drives continuous renewal of the interfacial atomic configuration and sustains high activity in hydrogen halide splitting and hydrogen production over multiple cycles. This work provides fundamental insights into adaptive catalytic interfaces and suggests new pathways for smart photocatalyst engineering via dynamic material-light interplay. © 2026 The Author(s). Advanced Materials published by Wiley-VCH GmbH.truedynamic reconfigurationhalide perovskiteintermittent lightsingle-atom catalystsoft ionic latticejournal article10.1002/adma.2025185572-s2.0-105032408159