Abstract
NH3 treatment for nitrogen doping to metal oxides is widely used as a method of band gap narrowing. However, PH3 treatment of titanium dioxide(TiO2) powders has not yet been established. In the present study, PH3 treatment of TiO2 was attempted by heating TiO2 powders and solid-state sodium hypophosphite in a sealed ampoule. The color of the powders changed from colorless for untreated TiO2 to beige for TiO2 treated at 250, 290, 350 °C, or to gray for TiO2 treated at 450 °C. X-ray photoelectron spectroscopy (XPS) analysis of the treated TiO2 revealed that the phosphorus was in a phosphate form and that a part of Ti4+ in TiO2 was reduced to Ti3+. The absorption spectra and the XPS data suggested the generation of oxygen vacancies. Adsorption experiments of methylene blue and Eosin Y onto the treated TiO2 indicated the presence of phosphate on the surface of TiO2. X-ray diffraction (XRD) analysis indicated that the crystallite sizes of the treated TiO2 increased with increasing in temperature. Photodegradation rates of the pigments by the treated TiO2 under UV light depended on phosphate, oxygen vacancy and crystallinity. PH3 treatment of crystalline TiO2 were found to give priority to phosphate formation in contrast to NH3 treatment for nitrogen doping.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
