Effects of Boron Doping on Photocatalytic Activity and Microstructure of Titanium Dioxide Nanoparticles

Boron-doped TiO2 nanoparticles were prepared by the sol-gel method and characterized by XRD, TEM, XPS, FT-IR, and UV-vis spectroscopy. XRD results showed that the doping of boron ions could efficiently inhibit the grain growth and facilitate the anatase-torutile transformation prior to the formation of diboron trioxide phase. FT-IR and XPS results revealed that the doped boron was present as the form of B3+ in B-doped TiO2 samples, forming a possible chemical environment like Ti-O-B. The lattice parameters at different boron contents and calcination temperatures indicated that B3+ was likely to weave into the interstitial TiO2 structure. The photocatalytic activity of the B-doped TiO2 nanoparticles was evaluated by the photoregeneration of reduced nicotinamide adenine dinucleotide (NADH). All B-doped TiO2 nanoparticles calcined at 500 °C showed higher photocatalytic activity than pure TiO2 sample in the photocatalytic reaction of NADH regeneration under UV light irradiation. When the molar ratio of B to Ti was 5%, the TiO2 nanoparticles could photocatalytically reproduce 94% NADH.