Bifunctional property of Pt nanoparticles deposited on TiO2 for the photocatalytic sp3C–sp3C cross-coupling reactions between THF and alkanes

Abstract

The photocatalytic sp³C–sp³C cross-coupling between tetrahydrofuran (THF) and various alkanes was accomplished with Pt loaded titanium oxide (Pt/TiO₂) photocatalysts. The cross-coupling between THF and cyclohexane was systematically studied, which revealed that the reaction followed two routes: the main course was the photooxidation of both substrates on a Pt/TiO₂ photocatalyst to generate radical species followed by their successive coupling; meanwhile, the minor one was a hybrid of photocatalysis by Pt/TiO₂ and thermocatalysis by Pt metal nanoparticles. The activity of the Pt catalysis was suggested to consist in the activation of an sp³C–H bond in THF or alkane molecules adsorbed on its surface and promote the reaction between the activated molecules and photogenerated radical species. Thus, the Pt nanoparticles on TiO₂ were believed to play a bifunctional role of an electron receiver as well as a metal catalyst.