The Photocatalytic Activity of the Bi2O3-B2O3-ZnO-TiO2 Glass Coating

Abstract

Due to the low melting temperature, the glazes based on the Bi₂O₃-B₂O₃-ZnO system are used as coatings on the surface of industrial glass substrates. Moreover, the composition of these coatings does not contain PbO, meeting the optical and environmental properties requirements. In this study, TiO₂ was used in the Bi₂O₃-B₂O₃-ZnO glaze system to improve its photocatalytic ability. This can be considered a four – component glass system Bi₂O₃-B₂O₃-ZnO-TiO₂. The heating microscopy results show that the melting temperature of the glaze system is 606 °C. The Fourier transform infrared spectroscopy results show that the TiO₂ polyhedra are located independently in the structure without participating in forming a glass network. Thanks to that, the photocatalytic properties of TiO₂ are maintained. The X-ray diffraction patterns results show that the formed TiO₂ nanocrystals are rutile and anatase crystals. The results of determining the band gap energy using UV-Vis show that the band gap energy of the base glaze system increases with the addition of TiO₂. The methylene blue decomposition results also showed that the ability to decompose organic increased when TiO₂ was added to the glaze coating. The characteristics such as melting temperature, microstructure, and photocatalytic capacity of Bi₂O₃-B₂O₃-ZnO-TiO₂ white glazes (5 and 10 % weight of TiO₂) also were indicated in this paper.