Pd modified defective HNb3O8 with dual active sites for photocatalytic coproduction of hydrogen fuel and value-added chemicals

Developing photocatalysts for coproduction of hydrogen fuel and valuable chemicals is highly desired but still challenging. Herein, Pd-modified defective HNb 3 O 8 photocatalyst (denote as Pd/HNb 3 O 8 -H 2 ) consisting of dispersive Pd sites and abundant surface oxygen vacancies (V O s) was prepared via the thermal treatment of Pd 2+ -incorporated HNb 3 O 8 in H 2 /Ar gas. The existence of Pd favors the formation of V O s on HNb 3 O 8 , enabling the synchronous construction of Pd and V O dual active sites. The spectroscopy and photoelectrochemical studies demonstrate the advantages of Pd/HNb 3 O 8 -H 2 photocatalyst in promoting the separation and migration of photoinduced charge carries. The Pd/HNb 3 O 8 -H 2 photocatalyst exhibits the outstanding performance toward photocatalytic proton reduction coupled with selective benzyl-alcohol oxidation , achieving the optimal production rates of H 2 and benzaldehyde as high as 3.17 and 2.76 mmol·g cat −1 h −1 , respectively. The experimental and theoretical investigations have expounded the synergistic mechanism of Pd and V O dual active sites in boosting photocatalytic coproduction of H 2 and benzaldehyde.