TiO2/Nb2O5/carbon xerogel ternary photocatalyst for efficient degradation of 4-chlorophenol under solar light irradiation

Author(s)

de Moraes, Nicolas Perciani ; Torezin, Fernanda Azzoni ; Juca Dantas, Gustavo Viegas ; Martins de Sousa, Juliana Giancoli ; Valim, Ricardo Bertholo ; Rocha, Robson da Silva ; Landers, Richard ; Gaetano Pinto da Silva, Maria Lucia ; Rodrigues, Liana Alvares

• Document type: Journal article
• Source: CERAMICS INTERNATIONAL; v. 46, n. 10, p. 11-pg., 2020-07-01.

Abstract

This study examines the development of ternary photocatalysts based on titanium dioxide, niobium oxide, and carbon xerogel, aimed at increasing photocatalytic efficiency under solar light irradiation. The modifications proposed are focused on diminishing charge recombination and enhancing visible light sensitivity. The new photocatalyst was prepared using discarded titanium and niobium scraps and chips, whilst black wattle tannin was used as the carbon source. The X-ray diffractometry results show that the anatase form of titanium dioxide is present in the samples, whereas the niobium oxide presents itself in the amorphous structure. The incorporation of both carbon xerogel and niobium oxide into the TiO2 is confirmed by the infrared and energy dispersive spectroscopies. The diffuse reflectance results show that the materials containing carbon xerogel present a significantly higher visible light absorption, whilst the combined effect of the modifications proposed caused the gap energy of the ternary material to drop noticeably. The photocatalytic efficiency of the ternary material was superior to the ones found for the pure oxides and binary material, probably due to its lower value of bandgap and enhanced charge separation efficiency, as confirmed by the electrochemical impedance tests. (AU)

• FAPESP's process: 18/16360-0 - Development of ZnO/Bi2O3/Carbon xerogel ternary composites as photocatalysts for the degradation of persistent organic pollutants
• Grantee: Nicolas Perciani de Moraes
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/12035-7 - Mechanical and antimicrobial properties of Ag/PMMA nanocomposite
• Grantee: Gilmar Patrocínio Thim
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/10492-1 - Photocatalytic evaluation of heterojunctions semiconductor/ZnO/carbon xerogel in the photodegradation of 4-chlorophenol in both fluidized bed and batch reactors
• Grantee: Liana Alvares Rodrigues
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/10118-0 - Study and application of electrochemical technology for the analysis and degradation of endocrine interferents: materials, sensors, processes and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/02762-5 - Development of technologies to prevent pollution: degradation and monitoring online of antibiotics in sewage
• Grantee: Robson da Silva Rocha
• Support Opportunities: Research Grants - Young Investigators Grants