Unusual photocatalytic materials with UV-VIS-NIR spectral response: deciphering the photothermocatalytic synergetic effect of Pt/LaVO4/TiO2

Abstract

In the present paper, we propose a new type of catalyst, Pt/LaVO₄/TiO₂ (PLVT), which combines the use of UV and visible light for photocatalysis on LaVO₄/TiO₂ (LVT) and the heating effect of infrared light for low-temperature thermocatalysis on Pt. Under simulated solar light, benzene as an objective pollutant can be 100% eliminated and converted into CO₂ and H₂O on PLVT at 70 °C with an obvious synergetic effect of photocatalysis and thermocatalysis. The photothermocatalytic activity at 70 °C is about three times the sum of the photocatalytic activity and thermocatalytic activity. The stable performance of PLVT in a 60 hour durability test also indicates its applicable potential. The roles of Pt and LVT in the synergetic effect are discussed by comparing PLVT with control samples regarding the interaction between Pt and LVT under photothermocatalytic conditions. On the basis of the above experimental results, a possible mechanism of the synergetic effect is proposed.