Site-Selective Pt Anchoring on Oxygen Vacancies by Atomic Layer Deposition Promotes Metal–Acid Synergy for Enhanced Guaiacol Hydrodeoxygenation

For metal–acid bifunctional catalysts, accurately tuning the spatial distribution of catalytic sites and enhancing the metal–acid synergy remain a challenge. To this end, we combine oxygen vacancy (O v ) engineering with atomic layer deposition (ALD) on Nb 2 O 5 ·nH 2 O to simultaneously achieve highly dispersed Pt, enhanced Brønsted acid site (BAS) concentration, and optimized metal–acid synergy. Specifically, for the Pt/O v -Nb 2 O 5 ·nH 2 O catalyst, the abundant O v s formed in the O v -Nb 2 O 5 ·nH 2 O via H 2 heat treatment guide more ALD Pt selective anchoring, thus forming smaller Pt clusters. Additionally, Pt species on the O v s intensify local NbO 6 distortion, inducing more BASs. These acid sites are in close proximity to Pt species, enhancing metal–acid synergistic catalysis. By contrast, Pt/Nb 2 O 5 ·nH 2 O, prepared by directly depositing Pt on Nb 2 O 5 ·nH 2 O, exhibits a larger Pt cluster size and lower BAS concentration. Consequently, Pt/O v -Nb 2 O 5 ·nH 2 O exhibits efficient guaiacol conversion and higher cyclohexane selectivity than Pt/Nb 2 O 5 ·nH 2 O in guaiacol hydrodeoxygenation (HDO). This endeavor offers guidelines for the rational design of metal–acid bifunctional catalysts.