Preparation and photocatalytic properties of rutile TiO2 with a unique morphology and SrTiO3–TiO2 composites obtained by acid treatment of SrTiO3

Publication date: Available online 11 January 2020Source: Materials Research BulletinAuthor(s): Sayaka Yanagida, Kiyoto Sano, Takahiro Takei, Nobuhiro KumadaAbstractIn this work, rutile, anatase, and SrTiO3–TiO2 composites were prepared by acid treatment of SrTiO3 using various concentrations of HNO3 at 90 °C. The product of the acid treatment depended on the acid concentration: fine TiO2 (anatase) particles were obtained for 0.5 M, a mixture of anatase- and rutile-phase TiO2 was obtained for 1 M, and large dumbbell-like TiO2 (rutile) particles were obtained for 2, 3, and 4 M HNO3. Furthermore, SrTiO3–TiO2 (anatase) composites in which fine TiO2 (anatase) particles formed on SrTiO3 cores were produced by a short-duration acid treatment. The composite exhibited a higher photocatalytic activity than the SrTiO3, TiO2 (anatase), TiO2 (rutile), and mixture of anatase- and rutile-phase TiO2 in methylene blue decomposition. The hybridization of SrTiO3 and anatase with a large contact area was considered to prevent rapid electron–hole charge recombination and to enhance the photocatalytic activity of the composites.Graphical abstract
Source: Materials Research Bulletin - Category: Materials Science Source Type: research