Oxygen vacancy confining effect on photocatalytic efficiency of Pt₁-black TiO₂ single-atom photocatalysts for hydrogen generation and phenol decomposition

Energy and pollution are major issues worldwide, calling for advanced techniques of biofuel production and environmental remediation, such solar photocatalysis. Engineering the co-catalyst at atom level has recently been proposed to increase the photocatalytic efficiency. Here, we report a new strategy for preparing highly stable single-atom photocatalysts containing abundant isolated atomic sites. We used oxygen vacancies (Vos) to confine Pt atoms and to produce single-atom photocatalysts, labeled Pt_0.254/black TiO₂, that are more efficient and more stable. Results show that Pt atoms are mainly located on surface oxygen vacancies and are rather uniformly distributed on the surface of black TiO₂ at a concentration of 0.254 wt %. The single-atom photocatalyst displayed excellent catalytic efficiency and stability for hydrogen generation and phenol decomposition. Overall, our findings propose an alternative method to fabricate and engineer single-atom photocatalysts.