Effect of Nb/C ratio in the morphological, structural, optical and photocatalytic properties of novel and inexpensive Nb2O5/carbon xerogel composites

Autor(es)

de Moraes, Nicolas Perciani ^[1] ; Bacani, Rebeca ^[2] ; Caetano Pinto da Silva, Maria Lucia ^[1] ; Bastos Campos, Tiago Moreira ^[3] ; Thim, Gilmar Patrocinio ^[3] ; Rodrigues, Liana Alvares ^[1]

Afiliação do(s) autor(es)

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

^[2] Univ Sao Paulo, EEL, Dept Engn Mat, Estr Municipal Campinho S-N, BR-12602810 Lorena, SP - Brazil

^[3] CTA, ITA, Praca Mal Eduardo Gomes 50, BR-12228900 Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CERAMICS INTERNATIONAL; v. 44, n. 6, p. 6645-6652, APR 15 2018.
• Citações Web of Science: 9

Resumo

This work explores the development of hybrid Nb2O5/carbon xerogel photocatalysts. The precursor materials used, such as tannin and recycled niobium scraps, enhance the economic and environmental aspects of the synthesis. The materials were characterized by diffuse reflectance spectroscopy, scanning electron microscopy, dispersive energy spectroscopy, infrared spectroscopy, Raman spectroscopy and X-ray diffraction. The photo catalytic action of the material was evaluated by methylene blue decomposition as determined by UV visible spectroscopy. Anhydrous niobium oxide has a hexagonal structure. The X-ray profiles of the materials developed (XC-wNb) are similar to Nb2O5, confirming the presence of inorganic oxide in the matrix of these composites. The chemical elements that compose the samples are homogeneously distributed on the surface of the samples, confirming the dispersion of the oxide in the carbonaceous matrix. The XC-wNb absorbs radiation in a considerably wider range than inorganic oxides, in this case, for the entire wavelength range used in the experiments, thereby suggesting the synergistic effect of xerogel and niobium oxide on the optical properties of the XC-wNb samples. All XC-wNb presented photocatalytic activity under visible radiation, evidencing the beneficial coupling effect on the photocatalytic properties of the material. The XC-24Nb was the most effective photo catalyst at the wavelength used due its composition, morphological and photochemical properties. The methylene blue photodegradation is controlled to a greater extent by reaction with the OH' radical. The XC-24Nb also presents high stability and reusability, which are optimal properties for industrial application. (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