g-C3N4/Nb2O5 heterostructures tailored by sonochemical synthesis: Enhanced photocatalytic performance in oxidation of emerging pollutants driven by visible radiation

Author(s)

da Silva, Gelson T. S. T. ; Carvalho, Kele T. G. ; Lopes, Osmando F. ; Ribeiro, Caue

• Document type: Journal article
• Source: APPLIED CATALYSIS B-ENVIRONMENTAL; v. 216, p. 70-79, NOV 5 2017.
• Web of Science Citations: 24

Abstract

In this study, g-C3N4/Nb2O5 heterostructures were successfully prepared by a sonochemical method based on surface charge -induced heteroaggregation. Under visible irradiation, the heterostructured gC(3)N(4)/Nb2O5 samples exhibited higher activity in the photooxidation of the drug amiloride (AML) and rhodamine B dye (RhB), compared to the pure g-C3N4 and Nb2O5 phases. The enhanced photocatalytic activity of the heterostructures could be attributed to the effective formation of heterojunctions between the g-C3N4 and Nb2O5 semiconductors, causing the migration of photogenerated electrons and holes, hence increasing their lifetimes. Formation of the type -II heterostructure was confirmed by time -resolved photoluminescence, in which the 3CN:1Nb heterostructure showed the longest electron/hole pair lifetime. The 3CN:1Nb and 1CN:3Nb heterostructures exhibited high stability even after four cycles of reuse in RhB dye and drug AML oxidation, respectively. In summary, the combination of g-C3N4 with Nb2O5 to produce a type -II heterostructure is a good strategy to overcome important challenges in photocatalysis. (C) 2017 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 16/09746-3 - Electro-/Photoelectrocatalysis reduction of CO2: efficiency, selectivity and oscillatory kinetics
• Grantee: Osmando Ferreira Lopes
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 15/12304-0 - Evaluation of the photocatalytic activity of g-C3N4/Nb2O5 heterojunctions in the abatement of pollutants in gas phase
• Grantee: Kele Tatiane Gomes Carvalho
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 13/13888-0 - Synthesis of BiVO4/bismuth oxides nano-heterostructures and evaluation of photocatalytic properties
• Grantee: Osmando Ferreira Lopes
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/17639-4 - Obtainment of nanostructured semiconductors: correlation of the photocatalytic properties to their structural characteristic
• Grantee: Waldir Avansi Junior
• Support type: Regular Research Grants