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• In 2 S 3 /WO 3 S-scheme heterojunctions were constructed by a facile self-assembly method. • Internal electric field is built at In 2 S 3 /WO 3 interfaces owing to work function difference. • S-scheme charge transfer and separation mechanism was verified by in situ XPS and DFT calculations. • In 2 S 3 /WO 3 achieves enhanced photocatalytic H 2 evolution and nitrobenzene hydrogenation. Solar energy conversion and high-value chemical production are of utmost importance. However, the development of efficient photocatalysts with strong redox ability remains challenging. Here we report a unique 3D/0D In 2 S 3 /WO 3 S-scheme heterojunction photocatalyst obtained by depositing WO 3 quantum dots (QDs) onto hierarchical In 2 S 3 microflowers. The In 2 S 3 /WO 3 composite exhibits outstanding visible light absorption, with a maximum optical response of up to 600 nm. The electronic interaction and charge separation at interfaces are explored by in situ X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. The difference in work function causes In 2 S 3 to donate electrons to WO 3 upon combination, leading to the formation of an internal electric field (IEF) at the interfaces. Due to the IEF and bent energy bands, the transfer and separation of photogenerated charge carriers follow an S-scheme pathway within In 2 S 3 /WO 3. Owing to the strong redox ability, spatial charge separation and lower H 2 -generation barrier of S active sites, the optimized In 2 S 3 /WO 3 heterojunctions show enhanced photocatalytic hydrogen evolution of 0.39 mmol h–1 g–1, 6.7 times that of pristine In 2 S 3. In addition, the In 2 S 3 /WO 3 S-scheme heterojunctions afford a remarkable activity for photocatalytic nitrobenzene hydrogenation with nearly 98% conversion and 99% selectivity of aniline within 1 h. Our work might present new insights into developing efficient S-scheme heterojunctions for various photocatalytic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, we investigate Mn-doped CeO2nanoribbons as photocatalysts to address the issue of performance enhancement in volatile organic compounds (VOCs) removal. Our primary focus centers on elucidating the interplay between charge rearrangement and local electric field (LEF) effects to uncover how these key factors collectively contribute to the improved photocatalytic performance. The successful doping of Mn atoms into the CeO2lattice resulted in a strong dopant/matrix interaction effect. In situ XPS and density functional theory (DFT) calculations confirmed significant local charge rearrangement due to the dopant-induced local electric field, promoting charge carrier separation. The Mn dopant facilitated the generation of superoxide and hydroxide radicals. DFT simulations showed that Mn doping promoted VOCs adsorption on CeO2, favoring the subsequent oxidation process. The Mn-doped CeO2nanoribbons achieved enhanced photodegradation performance of HCHO and CH3COCH3compared to CeO2. This work aims to provide guidance and insights for the development of advanced photocatalysts.