Preparation and photocatalytic properties of rutile TiO2 with a unique morphology and SrTiO3–TiO2 composites obtained by acid treatment of SrTiO3. (May 2020)

• Record Type: Journal Article
• Authors: Yanagida, Sayaka; Sano, Kiyoto; Takei, Takahiro; Kumada, Nobuhiro
• Is Part Of: Materials research bulletin. Volume 125(2020)
• Publication Date: 2020-05
• Subjects: Acid treatment -- SrTiO3 -- TiO2 -- Photocatalyst -- Composite; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2019.110762
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Anatase- and rutile-phase TiO2 was formed by SrTiO3 acid dissolution. The crystalline phase of the formed TiO2 is dependent on the HNO3 concentration. SrTiO3 –TiO2 composite particles can be prepared by a short-duration acid treatment. In the composite, fine TiO2 (anatase) particles formed on the SrTiO3 core. SrTiO3 –TiO2 composites exhibited higher photocatalytic activities. Abstract: In 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.