The construction of step scheme (S-scheme) heterojunction with a great redox ability and a high charge transfer efficiency is an effective strategy to enhance the photocatalytic activity. ZnIn₂S₄ nanosheets were grown in-situ on the surface of perylenimide (PDI) rods via a solvothermal method. A PDI/ZnIn₂S₄ heterojunction exhibits an excellent photocatalytic performance due to its tight interfacial contact and matched band structures. Moreover, the 5% PDI/ZnIn₂S₄ affords high H₂/benzaldehyde production rates of 21.66 mmol/(g·h) and 1.02 mmol/(g·h), respectively, which is 2.12 and 3.00 folds of pristine ZnIn₂S₄, respectively when coupling the photocatalytic H₂ evolution and the benzyl alcohol oxidation in the reaction system. Based on the results by X-ray photoelectron spectroscopy, transient photoluminescence spectroscopy and electron paramagnetic resonance analysis, the formation of the built-in electric field at the interface of PDI/ZnIn₂S₄ and the S-scheme electron transfer path was confirmed. The enhanced photocatalytic performance and stability can be attributed to the close contact and rich active sites of PDI/ZnIn₂S₄, and the charge carrier migration and increased photoredox properties were improved by a S-scheme charge-transfer route. This organic–inorganic PDI/ZnIn₂S₄ S-scheme heterojunction photocatalyst can be used as a novel bifunctional photocatalyst in converting solar light into clean fuel and chemicals.

Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance, but the fast recombination of photogenerated carriers in photocatalysts seriously decreases the conversion efficiency. Herein, a novel dual-functional 0D Cd_0.5Zn_0.5S/2D Ti₃C₂ hybrid was fabricated by a solvothermally in-situ generated assembling method. The Cd_0.5Zn_0.5S nano-spheres with a fluffy surface completely and uniformly covered the ultrathin Ti₃C₂ nanosheets, leading to the increased Schottky barrier (SB) sites due to a large contact area, which could accelerate the electron-hole separation and improve the light utilization. The optimized Cd_0.5Zn_0.5S/Ti₃C₂ hybrid simultaneously presents a hydrogen evolution rate of 5.3 mmol/(g·h) and a benzaldehyde production rate of 29.3 mmol/(g·h), which are ~3.2 and 2 times higher than those of pristine Cd_0.5Zn_0.5S, respectively. Both the multiple experimental measurements and the density functional theory (DFT) calculations further demonstrate the tight connection between Cd_0.5Zn_0.5S and Ti₃C₂, formation of Schottky junction, and efficient photogenerated electron-hole separation. This paper suggests a dual-functional composite catalyst for photocatalytic hydrogen evolution and benzaldehyde production, and provides a new strategy for preventing the photogenerated electrons and holes from recombining by constructing a 0D/2D heterojunction with increased SB sites.