Novel synthetic route for low-cost carbon-modified TiO2 with enhanced visible light photocatalytic activity: carbon content and calcination effects

Autor(es)

de Moraes, Nicolas Perciani ^[1] ; Caetano Pinto da Silva, Maria Lucia ^[1] ; Bastos Campos, Tiago Moreira ^[2] ; Thim, Gilmar Patrocinio ^[2] ; Rodrigues, Liana Alvares ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, EEL, Dept Engn Quim, Estr Municipal Campinho S-N, BR-12602810 Sao Paulo - Brazil

^[2] CTA, ITA, Praca Mal Eduardo Gomes 50, BR-12228900 Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Sol-Gel Science and Technology; v. 87, n. 2, p. 380-390, AUG 2018.
• Citações Web of Science: 2

Resumo

The aim of this study was the development of low-cost tannin-formaldehyde xerogel/TiO2 (XTi-w) and carbon xerogel/TiO2 (XTiC-w) photocatalysts. The materials used as precursors were recycled titanium scraps and black wattle tannin extract, highlighting the low-cost approach employed in the synthesis. The materials were characterized by diffuse reflectance spectroscopy, scanning electron microscopy, dispersive energy spectrophotometry, X-ray diffractometry, infrared and Raman spectroscopy. X-ray diffractometry showed that the XTiC-w have tetragonal crystalline structure (anatase), whereas the XTi-w has an amorphous structure. The Raman and infrared analysis also showed the presence of titanium dioxide in the composition of both XTi-w and XTiC-w. XTi-w and XTiC-w showed photocatalytic activity at the visible wavelength. Titanium dioxide displayed no photocatalytic activity at the visible wavelength. The XTi-60 composite displayed the highest efficiency in the removal of the methylene blue from the system, as well as good reusability properties. The radicals with higher influence in the photocatalytic reaction mechanism are the photo generated electron and the singlet oxygen molecule. The effect of the heat treatment is negative on the photocatalytic properties of the hybrids produced, due to the removal of acid sites, adsorbed water and OH surface groups. {[}GRAPHICS] Hybrids were produced using low-cost materials, such as titanium scraps and tannin Both hybrid materials showed photocatalytic activity at the visible wavelength Heat treatment is negative on the photocatalytic properties of the hybrids Reaction mechanism is controlled by trapped electrons and singlet oxygen molecules. (AU)

• Processo FAPESP: 15/08995-7 - Preparação, modificação e avaliação catalítica de fotocatalisadores à base de Nb2O5
• Beneficiário: Liana Alvares Rodrigues
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/04244-0 - Preparação, modificação e avaliação catalítica de fotocatalisadores híbridos TiO2/xerogel de carbono
• Beneficiário: Nicolas Perciani de Moraes
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica