Photocatalytic H₂ Generation: Controlled and Optimized Dispersion of Single Atom Co‐Catalysts Based on Pt‐TCPP Planar Adsorption on TiO₂

Abstract

Abstract When using single atoms (SAs) as a co‐catalyst in photocatalytic H 2 generation, achieving a well‐dispersed, evenly distributed and adjustable SA surface density on a semiconductor surface is a challenging task. In the present work we use the planar adsorption of tetrakis‐(4‐carboxyphenyl)‐porphyrin (TCPP) and its platinum coordinated analogue, Pt‐TCPP, onto anatase TiO 2 surfaces to establish a spatially controlled decoration of SAs. We show that the surface Pt SA density can be very well controlled by co‐adsorption of Pt‐TCPP and TCPP in the planar monolayer regime, and by adjusting the Pt‐TCPP to TCPP ratio a desired well dispersed surface density of SAs up to 2.6×10 5 atoms μm −2 can be established (which is the most effective Pt SA loading for photocatalysis). This distribution and the SA state are maintained after a thermal treatment in air, and an optimized SA density as well as a most active form of Pt for photocatalytic H 2 evolution can be established and maintained.