Novel TiO2 prepared from titanyl sulphate by using pressurized water processing and its photocatalytic activity evaluation. (November 2017)

• Record Type: Journal Article
• Authors: Matějová, Lenka; Polách, Lukáš; Lang, Jaroslav; Šihor, Marcel; Reli, Martin; Brunátová, Tereza; Daniš, Stanislav; Peikertová, Pavlína; Troppová, Ivana; Kočí, Kamila
• Is Part Of: Materials research bulletin. Volume 95(2017)
• Page Start: 30
• Page End: 46
• Publication Date: 2017-11
• Subjects: TiO2 -- Titanyl sulphate -- Pressurized water processing -- Microstructure -- Photoactivity; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2017.07.010
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: A novel preparation approach of TiO2 anatase from titanyl sulphate by using pressurized water processing. Processing temperature affects crucially the TiO2 anatase crystallization. Correlation between Raman FWHMs and XRD determined anatase crystallites-size enabling the estimation of anatase crystallites-size from Raman spectra. The anatase crystallite-size and surface area are determining properties in AO7 photo-discolorization. The band gap structure and rate of recombination of electrons and holes are the determining properties in N2 O photodecomposition. Abstract: TiO2 anatase was prepared by a novel preparation approach, combining utilization of titanyl sulphate as a precursor and pressurized water processing. In addition, two different chemical methods for preparation were used – thermal hydrolysis and induced hydrolysis. The photoactivity of developed TiO2 was examined in two environmentally-prospective reactions: azo-dye AO7 photodiscoloration (oxidation) and N2 O photodecomposition (reduction). It was revealed that during the processing the temperature has a crucial effect on TiO2 crystallization contrary to pressure. TiO2 anatase of smaller crystallite-size showed significantly higher photoactivity in AO7 photodiscoloration than TiO2 anatase of large crystallite-size. However, in N2 O photodecomposition all synthesized materials showed comparable activity. While the TiO2 anatase crystallite-size and surface area are the determining properties in azo-dye AO7 photodiscoloration, the electronic band structure and recombination rate of electron and holes are determining in N2 O photodecomposition. The correlation enabling the estimation of TiO2 anatase crystallite-size from Raman FWHMs was found as well.