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Despite the significant milestones in the half‐reduction process of photocatalysis, challenges remain in fully utilizing electron–hole pairs in the simultaneous redox reactions. Herein, a Z‐scheme ZnIn2S4/W18O49 (ZW) hybrid with complementary band edge potential is in situ constructed. The resultant fuzzy 1D‐assembled sea‐urchin photocatalyst demonstrates an optimal H2 and benzaldehyde yield of 122 and 106 µmol h−1 under λ > 420 nm light irradiation. This sacrificial‐agent‐free system entails solar‐to‐hydrogen (STH) and apparent quantum efficiency (AQE) values of 0.466% and 2.48% (420 nm), respectively, surpassing most of the recently reported photocatalytic systems without the aid of noble metal cocatalysts. The outstanding performance is mainly attributed to the synergistic formation of intimate Z‐scheme heterojunction and the induction of localized surface plasmon resonances. Comprehensive characterization studies prove the direct injection of energetic hot electrons to promote the number of long‐lived active electrons. Besides, electron paramagnetic resonance and scavenger tests clarify the complicated mechanistic puzzle of the dual‐redox reaction, where benzaldehyde is formed dominantly via O─H activation followed by C─H cleavage of benzyl alcohol over ZW hybrid. Lastly, the universal use of the ZnIn2S4/W18O49 composites is testified in various dual‐redox systems. This study offers a novel outlook for designing dual‐functioning heterojunctions toward a feasible photoredox application. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of carbon dioxide (CO2) into value‐added fuels is a vastly promising anthropogenic chemical carbon cycle to combat the greenhouse effect while meeting the ever‐increasing energy demand. Recently, lead‐based halide perovskites have demonstrated great potential in various applications including photochemical reduction of CO2. However, in view of lead toxicity, the exploration of a lead‐free alternative is crucial for long term application. Herein, a series of lead‐free mixed halide perovskites Cs3Sb2ClxBr9−x (0 ≤ x ≤ 9) is prepared via a facile antisolvent recrystallization technique, where the incorporation of a secondary halide enhances the charge transfer and separation while allowing precise tuning of bandgap between 2.59 and 2.90 eV. Theoretical calculations further reveal that the formation of mixed Cl/Br halides engenders favorable charge redistribution due to lower octahedral distortion, which in turn strengthens CO2 adsorption and activation. Under visible light illumination, the optimal dual halide perovskite, Cs3Sb2Cl4Br5 manifests substantial twofold and fourfold enhancements of CH4 yield over the single halide perovskite, Cs3Sb2Br9 and Cs3Sb2Cl9, respectively. In brief, this study provides a compelling demonstration of lead‐free mixed halide perovskites for photocatalytic CO2 reduction, and it is anticipated to drive further application of perovskite‐based photocatalysts toward a diverse range of artificial photoredox reactions. [ABSTRACT FROM AUTHOR]