Synthesis of perovskite-based structures for application as electrocatalysts for in situ H2O2 electrogeneration and degradation of Fipronil and Cypermethrin

• Grant number: 25/04515-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: October 01, 2025
• End date: September 30, 2030
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Principal Investigator: Marcos Roberto de Vasconcelos Lanza
• Grantee: Larissa Fernandes
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 22/12895-1 - Advanced processes for the degradation of emerging pollutants: catalytic materials, electroanalytical sensors and scientific dissemination, AP.TEM

Abstract

Several contaminant compounds, such as pharmaceuticals and insecticides, are not completely degraded and mineralized by traditional treatment methods. As an alternative method, electrochemical technology based on Advanced Oxidative Processes (AOPs) has emerged. These processes are based on the in situ production of active radical species, such as the hydroxyl radical (*OH), which is highly reactive and efficient in the degradation of chemical compounds. The electrochemical generation of H2O2 through the Oxygen Reduction Reaction (ORR) via 2 electrons (ORR 2e-) is a precursor of *OH. The use of electrocatalysts as modifiers of the carbonaceous matrix to accelerate and optimize the generation of this radical in situ is the subject of intense studies in the literature. In this sense, perovskite oxides of the LaBO3 type have stood out as promising electrocatalysts due to their highly stable crystalline structure and versatility in chemical composition. The flexibility in the substitution of B-site cations allows the formation of redox pairs and oxygen vacancies, favoring the adsorption of molecular oxygen and application in RRO 2e¿. The incorporation of these oxides in carbonaceous matrices increases the electrical conductivity and stability of the material, enhancing its catalytic performance, but it is still little explored in the literature. In this sense, this project proposes the development of electrocatalysts based on perovskite structures of the AB1-yB'yO3 type (B = Fe, Mn, Ni) as modifiers of Printex carbon (L6, XE2B and HiBlack) for in situ H2O2 electrogeneration. In this step, the gas diffusion electrode (GDE) will be used to increase the electrocatalytic efficiency in the promotion of several radical species for application in the degradation of the multi-action compounds, Fipronil and Cypermethrin, at different pH values. (AU)