Hydrogen peroxide route to Sn-doped titania photocatalysts

Abstract

BackgroundThe work aims at improving photocatalytic activity of titania under Vis light irradiation using modification by Sn ions and an original, simple synthesis method. Tin-doped titania catalysts were prepared by thermal hydrolysis of aqueous solutions of titanium peroxo-complexes in the presence of SnCl4 or SnCl2 using an original, proprietary "one pot" synthesis not employing organic solvents, metallo-organic precursors, autoclave aging nor post-synthesis calcination. The products were characterized in details by powder diffraction, XPS, UV–vis, IR, and Raman spectroscopies, electron microscopy and surface area and porosity measurementsResultsThe presence of tin in synthesis mixtures favors the formation of rutile and brookite at the expense of anatase, decreases the particle size of all formed titania polymorphs, and extends light absorption of titania to visible light region >400 nm by both red shift of the absorption edge and introduction of new chromophores. The photocatalytic activity of titania under UV irradiation and >400 nm light was tested by decomposition kinetics of Orange II dye in aqueous solutionConclusionsDoping by Sn improves titania photoactivity under UV light and affords considerable photoactivity under >400 nm light due to increased specific surface area and a phase heterogeneity of the Sn-doped titania powders.

Behaviors of helium in Cr2AlC from first principles

“…The results indicate that there is a positive correlation between the value of formation energy and the size of correspondent deformation volumes. Small deformation volume reflecting small lattice distortion causes the lower deformation energy in the doped systems, which is generally dependent on the classical concepts of elastic strain . In summary, He atom can most likely occupy the I AlC site in Cr 2 AlC for all selected four supercells, resulting in a decrease in the lattice distortion energy.…”

“…Small deformation volume reflecting small lattice distortion causes the lower deformation energy in the doped systems, which is generally dependent on the classical concepts of elastic strain. 34,35 In summary, He atom can most likely occupy the I AlC site in Cr 2 AlC for all selected four supercells, resulting in a decrease in the lattice distortion energy. The calculated formation energies and deformation volumes in other supercells show the same results.…”

Anthracycline antibiotics derivate mitoxantrone—Destructive sorption and photocatalytic degradation

“…The time dependence of mitoxantrone photocatalytic degradation (and kinetics of sorption on the titania surface) was fitted using Eq (1) ; alternatively, Eq (2) was modified for the first-order kinetics reaction [ 14 ]: where c is the concentration of mitoxantrone; c 0 is the initial concentration of mitoxantrone; and k, k 1 , and k 2 are the rate constants. A is a constant expressing the unreacted proportion of mitoxantrone.…”

h-BN-TiO2Nanocomposite for Photocatalytic Applications

“…The thermal hydrolysis of titania peroxo-complexes is a simple, low cost, and effective method for synthesis of the photocatalytic materials based on TiO 2 . This method was successfully used for synthesis of iodine- [11], titanium- [12] niobium-, and tantalum-doped titania [13] and also TiO 2graphene composite [3].…”