Grätzel‐Type TiO<sub>2</sub> Anatase Layers as Host for Pt Single Atoms: Highly Efficient and Stable Photocatalytic Hydrogen Production
Ujjaval Kerketta, Hyesung Kim, Nikita Denisov, Patrik Schmuki
Abstract
Abstract Single atoms (SAs) represent not only a new frontier in classic heterogeneous catalysis but are also increasingly investigated as co‐catalysts in photocatalytic reactions. In contrast to classic catalysis, many photocatalytic platforms require only a very low SA loading density to reach a saturated photocatalytic activity. As a result, an optimized light harvesting/carrier transport combination in the supporting semiconductor becomes the key aspect for the overall photocatalytic efficiency. In this work, it is demonstrated that Grätzel type mesoporous TiO 2 layers represent an ideal host for Pt single‐atoms (SAs) that allow for a highly effective photocatalytic H 2 generation. Using a layer with an optimized geometry, structure, as well as Pt SA loading, a photocatalytic H 2 production is achieved of up to ≈2900 µL h −1 (under irradiation at λ = 365 nm and I = 65 mW cm −2 ) – a performance that is far superior to previous Pt SA/TiO 2 structures based on TiO 2 nanotubes, nanosheets, or metal organic frameworks. Moreover, such SA/substrate combination provides a highly stable H 2 production over time. The present work thus introduces the use of this classic TiO 2 nanostructure as the most effective host for Pt SAs and its use for highly efficient photocatalytic H 2 production from aqueous solutions.