Reciprocal regulation between support defects and strong metal-support interactions for highly efficient reverse water gas shift reaction over Pt/TiO2 nanosheets catalysts

• The Pt/N-doped TiO 2 catalyst shows superior activity in the RWGS reaction. • The N-doped TiO 2 has more stable bulk Ti 3+ defects. • There is more paramount SMSI effect between Pt and the N-doped TiO 2 . • Defects and doped N enhance Pt dispersion; Pt promote defect replenishment in turn. • Bulk Ti 3+ migration leads to surface defect formation to stimulate RWGS reaction. Strong metal-support interaction (SMSI) is regarded as one of the most important concepts in heterogeneous catalysis; however, few researches are focused on SMSI regulating the support structure, properties and their roles on the catalytic performance. Herein, anatase TiO 2 {001} nanosheets pretreated in different atmosphere were used to load Pt for reverse water gas shift reaction. The Pt/N-doped TiO 2 catalysts exhibited significantly superior catalytic performance. The investigation demonstrated that defects and doped-N enhance the Pt dispersion while Pt and SMSI in turn promote defects regeneration during activation in H 2 . During reaction, surface defects enable CO 2 activation to generate active intermediates which easily decompose into CO. Furthermore, the small Pt particles and SMSI facilitate H 2 dissociative adsorption and spillover to replenish both surface defects and bulk Ti 3+ . Besides, a novel reaction route has been observed that the stable bulk Ti 3+ in N-doped TiO 2 migrate and transform to surface defects, enhancing catalytic performance.