Facile synthesis of Pt clusters decorated TiO2 nanoparticles for efficient photocatalytic degradation of antibiotics

Abstract

TiO₂ has attracted much attention in the field of photocatalytic degradation of antibiotics due to its good photostability, nontoxicity, and low cost. However, the rapid recombination of photogenerated carriers limits the further improvement of its photocatalytic activity. Here, a facile microwave-assisted hydrothermal method has been developed to prepare Pt clusters decorated TiO₂ nanoparticles. Pt clusters ranging in size from 1 to 2 nm are uniformly distributed across the surface of the TiO₂ matrix. A pronounced charge transfer phenomenon is discernible between the Pt and TiO₂ components. It is revealed that the charge transfer enables faster transfer and separation of photogenerated electrons and holes, which are beneficial for the improvement of photocatalytic degradation of both ofloxacin and levofloxacin. The degradation capability can be attributed to the efficient generation of •OH or •O₂⁻ species within the solution. The parallel adsorption model of TiO₂ on antibiotic molecules is verified, and the degradation reaction pathway has been elucidated. This work provides a facile method for optimizing the performance of TiO₂ photocatalysts, which can be extended to other oxide photocatalysts.