Pr doping promotes the formation of Pt single atoms by regulating metal-support interaction for remarkable photocatalytic hydrogen production

Abstract

Since the metal-support interaction (MSI) has a great influence on the structure and properties of single atom catalysts (SACs), the activity and stability of SACs can be effectively regulated by adjusting the structure of the matrix. Herein, the morphology of surface supported Pt species can be controlled by doping to adjust the properties of TiO2 support. Specifically, under the same conditions, the Pt species on the Pr doped TiO2 surface are Pt SAs (PtSA/TiO2(Pr)), while on the pure TiO2 surface are particles (PtNP/TiO2). Experimental and theoretical studies demonstrate that Pr doping weakens the interaction of Ti-O bond, stabilizes the O-Pt unit site and Pt SAs. Impressively, PtSA/TiO2(Pr) shows superior photocatalytic hydrogen production performance (196.43 mmol g-1h−1), far exceeding PtNP/TiO2 (91.96 mmol g-1h−1). Additionally, Pr dopant modulates the electronic interaction between TiO2 support and Pt SAs, thus the adsorption/desorption behavior of H intermediates (H*) is balanced. Besides, the electron delocalization of O adjacent to Pt SAs can be adjusted by Pr doping, prompting the establishment of efficient Pt-O electron transfer channels and further enhances the utilization of photogenerated carriers. This study presents a promising strategy to prepare SACs with high activity for photocatalyst hydrogen production.