In-situ assembled S‑scheme heterojunction of CsPbBr3 nanocrystals and W18O49 ultrathin nanowires for enhanced bifunctional photocatalysis

Coupling CO2 reduction with selective organic hydrocarbon oxidation using semiconductor photocatalysts holds significant importance in achieving carbon neutrality and obtaining valuable chemical raw materials. Nevertheless, finding a potential single photocatalyst with sufficient redox potentials capable of simultaneously driving redox reactions poses a formidable challenge. Herein, a distinct heterostructure of W18O49/CsPbBr3 was meticulously fabricated through the in-situ growing of CsPbBr3 nanocrystal on bundle-like W18O49 ultrathin nanowires via the hot-injection method. Experimental and theoretical characterizations reveal the establishment of a solid internal electric field at the heterojunction interface, enabling spatial charge separation via a valid interfacial S-scheme with strong redox ability. The W18O49/CsPbBr3 heterostructure demonstrated decent performance, yielding high production of CO (143 μmol g−1 h−1) and selective oxidizing toluene to benzaldehyde (1546 μmol g−1 h−1) with an 80% selectivity. This work may pave a rational way for fully exploiting the potentials of photogenerated carriers in the heterojunction photocatalysts in synergetic photocatalytic systems. [Display omitted] •An S-scheme heterostructure of W18O49/CsPbBr3 is designed via an in-situ growth method with spatial charge separation.•Remarkable bifunctional photocatalytic productions of CO and selective oxidizing toluene to benzaldehyde with high selectivity are achieved.•Comprehensive characterizations confirm that an effective S-scheme charge transfer mode is built.