Alkyl Groups-Modified Benzimidazole Copper Complexes-Derived Catalysts for the Electrocatalytic Reduction of Carbon Dioxide

• Grant number: 25/13879-8
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: September 01, 2025
• End date: August 31, 2029
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Fabio Henrique Barros de Lima
• Grantee: Guilherme Santos de Almeida
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 19/22183-6 - Electrocatalysis VI: fundamental and applied aspects of emerging and classical problems in electrochemical energy conversion, AP.TEM

Abstract

The electrochemical reduction of carbon dioxide (CO¿RR) has emerged as a promising process for utilizing atmospheric CO¿ to produce higher value-added chemical products. Numerous efforts have been devoted to the development of more active, selective, and stable electrocatalysts. Copper is, so far, the only metal with proven activity for the formation of C¿¿ products, such as ethylene and ethanol, although it suffers from limitations in terms of selectivity and stability. This project aims to investigate the electrocatalytic properties of [Cu(bzimpy)Cl¿]-based complexes (where bzimpy = 2,6-bis(2-benzimidazolyl)pyridine, a tridentate ligand) for CO¿RR. These complexes exhibit reversible restructuring after deactivation processes, allowing regeneration of the initial structure and thereby providing dynamic stability to the system. To advance the development of this class of electrocatalysts, it is essential to understand whether CO¿RR selectivity, in relation to the competing hydrogen evolution reaction (HER) from water reduction, can be modulated through structural modification of the complex with hydrophobic functional groups, such as alkyl chains. The synthesized electrocatalysts will be characterized using various techniques, including electron paramagnetic resonance (EPR) spectroscopy and X-ray absorption spectroscopy (XAS). Their activity, selectivity, and stability toward CO¿RR will be evaluated through online mass spectrometry and inline gas chromatography. (AU)