Single platinum atoms on TiO2 photocatalysts for acetaldehyde oxidation under visible-light irradiation

Abstract

The effects of incorporation of various amounts of Pt into TiO2 photocatalysts on the removal of acetaldehyde under visible light and 60% RH were investigated. Pt at 0.096 wt% boosted the photocatalytic efficiency of TiO2, while further increased Pt amount resulted in a decrease in activity. The enhanced activity can be ascribed to small amounts of Pt and dispersed individual Pt atoms on TiO2. Furthermore, among the 0.096 wt% Pt-TiO2 samples with diverse annealing temperatures (100, 130, 200, 375, and 525 °C), the 130 °C annealed sample exhibited the highest activity at various humidity values (0, 30, and 60% RH). This superior performance can be attributed to its unique single-Pt-atom structure coordinated with ammonia or ammonium species on a TiO2 lattice, as evidenced by TOF-SIMS results. Our findings show how unique photocatalytic structures alter catalytic activity by controlling Pt content and annealing temperatures, which will be critical for real-world applications. © 2024 Elsevier B.V.