Surface hydroxyl-induced Pt0 clusters on TiO2 for synergistic water gas shift catalysis

The regulation of active site electronic structure is a central strategy for optimizing supported metal catalysts, yet achieving precise and comprehensive control remains challenging due to the complex nature of metal-support interactions. This work presents a practical and reproducible approach to this challenge through the deliberate regulation of surface hydroxyls on TiO2 via a titanate-derived synthesis and controlled calcination, which correlates with improved water gas shift catalysis activity of Pt/TiO2 catalyst. The mechanistic interpretation by multiple characterizations suggest that a higher hydroxyl concentration is associated with the formation of more reduced Pt species, which enhanced CO activation. Subsequently, hydroxyl groups can be directly consumed by CO, which shows a correlation with the formation of oxygen vacancies. Catalysts with a higher density of oxygen vacancies exhibit stronger H2O dissociation capability. This work develops hydroxyl-content control as a viable strategy for catalyst optimization, supported by a mechanistic framework that rationalizes its impact on both metal electronic structure and oxide surface chemistry. Regulating the electronic structure of active sites is key to optimizing supported metal catalysts, yet precise control remains challenging. Here, the authors present a practical and reproducible strategy by tuning surface hydroxyls on TiO₂ via a titanate-derived synthesis and controlled calcination, leading to enhanced water–gas shift activity of Pt/TiO₂ catalysts.