Preparation and photocatalytic properties of BaZrO3 and SrZrO3 modified with Cu2O/Bi2O3 quantum dots

Abstract In this study, we report a novel method of BaZrO 3 and SrZrO 3 surface modification by two different types of quantum dots (QDs, Cu 2 O and Bi 2 O 3 ), which improved the photocatalytic performance of the obtained materials under UV-Vis light irradiation. Pristine BaZrO 3 and SrZrO 3 were prepared by the hydrothermal method. The deposition of Cu 2 O- and Bi 2 O 3 -QDs was carried out by chemical reduction. The morphology of the nanoparticles was estimated based on microscopic analysis (SEM, TEM). The perovskite structure and phase composition of polycrystals were confirmed by X-ray powder diffraction analysis (XRD). The elemental surface composition and the chemical character of detected elements were identified by X-ray photoelectron spectroscopy (XPS). The absorption ability and luminescence properties of nanocomposites were investigated by UV–Vis diffuse-reflectance spectroscopy (DRS UV-Vis) and luminescence spectroscopy. The influence of Cu 2 O/Bi 2 O 3 -QDs modification on the photocatalytic activity of BaZrO 3 and SrZrO 3 was evaluated by the phenol photodegradation process in the liquid phase under UV-Vis and toluene degradation in the gas phase under Vis irradiation. The highest photoactivity under UV-Vis light was observed for BaZrO 3 /1% Cu 2 O/33% Bi 2 O 3 and SrZrO 3 /1% Cu 2 O/33% Bi 2 O 3 samples. Research also demonstrated that single-type QD deposition (Cu 2 O or Bi 2 O 3 ) on the zirconate surface decreases the photoactivity in comparison with pristine zirconates. The mechanism of photocatalytic activity of the obtained nanocomposites was investigated by the formation of hydroxyl radicals under UV-Vis irradiation in the presence of terephthalic acid.