Development of photoanodes fabricated with bismuth vanadate for the photo-electrochemical degradation of nimesulide

• Grant number: 23/14186-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2024
• End date: January 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Fernando Cruz de Moraes
• Grantee: Esther Mara Angelini
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

In this work, the photo-electrochemical study and application of semiconductor materials for the degradation of the anti-inflammatory nimesulide will be proposed. Currently, semiconductor materials have become a very important tool for developing methods that aiming advanced oxidative processes coupled to electrochemical systems. The idea of these methods is to eliminate emerging contaminants in effluents, sewage and wastewater. In this context, this work will develop photoanodes fabricated with a film of semiconductor material bismuth vanadate, which will be deposited over a conductive glass surface. The produced photoanodes can be modified with metal oxide heterostructures. The purpose of which is to increase the system's photosensitization process. Studies will be carried out to optimize the method's parameters, such as: thickness of the bismuth vanadate film, type of metal oxides to be used as photosensitizer, wavelength of the radiating light, working potential, among others. The choice of the best parameters will be based on photocurrent measurements, using linear sweep voltammetry and chronoamperometry. The morphological, structural and optical characterizations of the photoanodes will be carried out using scanning electron microscopy techniques, transmission electron microscopy, energy dispersive diffraction of the selected area, X-ray diffraction and diffuse reflectance. The degradation of the nimesulide molecule will be monitored using spectroscopy in the UV-vis region and compared with mass spectrometry techniques. The photodegradation, electrodegradation and photo-electrodegradation processes will be evaluated to verify the influence of UVc radiation, at a potential value and time to be studied. Nimesulide concentration decay curves using a photo-electrodegradation system will be obtained and used to calculate the system's rate constant. Finally, the total organic carbon determination analysis will be carried out and, from this, the energy consumption for the degradation system will be estimated and the cost for removing 1.0 kg of nimesulide in wastewater will be calculated.