Inorganic Photocatalytic Enhancement: Activated RhB Photodegradation by Surface Modification of SnO2 Nanocrystals with V2O5-like species

SnO(2) nanocrystals were prepared by precipitation in dodecylamine at 100 °C, then they were reacted with vanadium chloromethoxide in oleic acid at 250 °C. The resulting materials were heat-treated at various temperatures up to 650 °C for thermal stabilization, chemical purification and for studying the overall structural transformations. From the crossed use of various characterization techniques, it emerged that the as-prepared materials were constituted by cassiterite SnO(2) nanocrystals with a surface modified by isolated V(IV) oxide species. After heat-treatment at 400 °C, the SnO(2) nanocrystals were wrapped by layers composed of vanadium oxide (IV-V mixed oxidation state) and carbon residuals. After heating at 500 °C, only SnO(2) cassiterite nanocrystals were obtained, with a mean size of 2.8 nm and wrapped by only V(2)O(5)-like species. The samples heat-treated at 500 °C were tested as RhB photodegradation catalysts. At 10(−7) M concentration, all RhB was degraded within 1 h of reaction, at a much faster rate than all pure SnO(2) materials reported until now

Functionalization of cotton by RGO/TiO2 to enhance photodegradation of rhodamine B under simulated solar irradiation

Reduced graphene oxide (RGO) and titanium dioxide (TiO2) nanoparticles were immobilized on cotton textile substrates to produce self-cleaning textiles. Varying number of layers of RGO andTiO(2) nanoparticles were coated by a facile method, and their photocatalytic potential was evaluated by measuring the degradation rate of rhodamine B (Rh-B) in an aqueous solution in a photoreactor under simulated solar irradiation. X-ray diffraction (XRD) and zeta potential measurements of starting materials were studied as they are crucial for innovative methods of functionalization. The study confirms that it is possible to ensure a good adhesion of nanoparticles on textile samples without the use of a resin. The application of varying number of RGO and TiO2 coatings has influence on photocatalytic properties of functionalized cotton textile substrates. The energy band gap of the samples reduces from 3.25 to -3.20 eV with the number of RGO coatings. All five de-ethylated intermediates of Rh-B during the photocatalytic degradation were identified using a high-performance liquid chromatography-mass spectrometry method. The experimental results show that, in general, the higher the number of RGO coatings is, the higher the photocatalytic efficiency (eta) of the functionalized substrate is (eta= 87% for three RGO coatings on TiO2).S. Landi Jr. expresses his gratitude to the Brazilian Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) for sporting his Doctoral Fellowship performed in Physics Centre at University of Minho. J. Molina wishes to thank the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) for the financial support. Moreover, the authors still want to thank the Portuguese Foundation for Science and Technology (FCT) for its contribution in financial support of this research work.info:eu-repo/semantics/publishedVersio