Triple heterojunction FTO/CuWO4|MnWO4|BiVO4 for enhanced photoelectrocatalytic degradation of antibiotic contaminants

Author(s)

Sales, Ana G. C. ; Lima, Aline E. B. ; Silva, Lara K. R. ; Libero, Laura O. ; Lima, Rayza B. ; Cavalcante, Laecio S. ; Mascaro, Lucia H. ; Luz Jr, Geraldo E.

• Document type: Journal article
• Source: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS; v. 724, p. 12-pg., 2025-11-05.

Abstract

The FTO/CuWO4|MnWO4|BiVO4 triple heterojunction photocatalyst was synthesized using spin coating and electrodeposition techniques. X-ray diffraction and Raman spectroscopy analyses revealed a triclinic crystal structure for CuWO4, while MnWO4 and BiVO4 exhibited monoclinic structures. Field emission scanning electron microscopy images of the films displayed distinct morphologies for each oxide and showed a thin film thickness of 594 nm. Mott-Schottky plots revealed the conduction band edge positions, showing a favorable cascade band alignment that minimized charge recombination and enhanced photostability. The triple heterojunction film showed an anodic photocurrent density of 56.2 mA/cm2 at 0.7 V vs. Ag/AgCl (1.23 V vs. RHE). Synergistic interactions between the components enhanced visible light absorption, with the absorption edge around 500 nm. Moxifloxacin degradation efficiencies of 23 % and 33 % were achieved within 165 min under solar-simulated light in the photocatalysis and photoelectrocatalysis systems, respectively. The applied bias suppressed charge recombination and eased the use of photogenerated carriers in catalytic reactions. Additionally, the films showed excellent stability, with only a 7 % reduction in photocatalytic efficiency after four reuse cycles. After reuse, simultaneous degradation of two antibiotics via photoelectrocatalysis using a solution prepared with river water was performed, achieving a degradation efficiency of 22.5 % for MOX and 17.0 % for MTZ. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/11986-5 - Generation and storage of New Energy: bringing technological development for the country
• Grantee: Ana Flávia Nogueira
• Support Opportunities: Research Grants - Research Centers in Engineering Program