Embedding Tandem Built‐in Electric Fields within Hollow Architectures for Enhanced Photothermal Effect in Alcohol Oxidation Coupled with H₂ Production

Abstract Rationally designing nanostructures based on a comprehensive understanding of structure‐property relationships is instrumental in enhancing the photothermal effect. Here, a general two‐stage morphology‐structure‐control strategy is presented to construct tandem built‐in electric fields (BIEFs) embedded hollow bifunctional photocatalysts (Sv‐chalcogenide hollow nanocage/NiCo₂S₄ heterojunctions, Sv represents sulfur vacancies, chalcogenides include ZnIn₂S₄, CdS, CdIn₂S₄). This strategy involves fabricating polyhedral cages via constraint epitaxy and embedding tandem BIEFs (consisting of intra‐component and inter‐component BIEF) within hollow nanocages through defect‐mediated heterocomponent anchorage. The resulting hollow nanoreactors synergize multilight scattering/reflection with directional charge‐transfer to boost photocarrier dynamics by stimulating plentiful carrier generation and driving continuous carrier localization and delocalized‐electron transportation. Subsequently, the localized surface plasmon resonance (LSPR)‐induced photogenerated electron excitation continuously collaborates with the intrinsic excitation for hot electron generation, thus improving the photothermal effect. Heterojunctions with efficient photothermal regulation optimize the pivotal intermediate adsorption/activation in selective alcohol oxidation coupled with H₂ evolution, delivering unprecedented reactivity and broad alcohol substrate compatibility. This study provides a programmable framework for structurally designing BIEFs within hollow architectures, elucidating the substantial impact of morphology‐structure control on photogenerated carrier dynamics and molecular catalytic behavior.