title: Facile oxidative conversion of TiH2 to high-concentration Ti(3+)-self-doped rutile TiO2 with visible-light photoactivity.
abstract: TiO2, in the rutile phase with a high concentration of self-doped Ti(3+), has been synthesized via a facile, all inorganic-based, and scalable method of oxidizing TiH2 in H2O2 followed by calcinations in Ar gas. The material was shown to be photoactive in the visible-region of the electromagnetic spectrum. Powdered X-ray diffraction (PXRD), transmission electron microscopy (TEM), ultraviolet-visible-near-infrared (UV-vis-NIR), diffuse reflectance spectroscopy (DRS), and Brunauer-Emmett-Teller (BET) methods were used to characterize the crystalline, structural, and optical properties and specific surface area of the as-synthesized Ti(3+)-doped rutile, respectively. The concentration of Ti(3+) was quantitatively studied by electron paramagnetic resonance (EPR) to be as high as one Ti(3+) per ~4300 Ti(4+). Furthermore, methylene blue (MB) solution and an industry wastewater sample were used to examine the photocatalytic activity of the Ti(3+)-doped TiO2 which was analyzed by UV-vis absorption, Fourier transform infrared spectroscopy (FT-IR), and electrospray ionization mass spectrometry (ESI-MS). In comparison to pristine anatase TiO2, our Ti(3+) self-doped rutile sample exhibited remarkably enhanced visible-light photocatalytic degradation on organic pollutants in water.
authors.affiliation: Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, USA.
authors.forename: Lauren R
authors.initials: LR
authors.lastname: Grabstanowicz
authors.forename: Shanmin
authors.initials: S
authors.lastname: Gao
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Robert M
authors.initials: RM
authors.lastname: Rickard
authors.forename: Tijana
authors.initials: T
authors.lastname: Rajh
authors.forename: Di-Jia
authors.initials: DJ
authors.lastname: Liu
authors.forename: Tao
authors.initials: T
authors.lastname: Xu