Understanding Water's Role on Ionic Liquids in CO2RR Systems Through in-situ Infrared Spectroscopy Analysis

• Grant number: 24/11931-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: November 30, 2024
• End date: November 29, 2025
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Roberto Manuel Torresi
• Grantee: Primaggio Silva Mantovi
• Supervisor: Angel Cuesta Ciscar
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Aberdeen, Scotland
• Associated to the scholarship: 21/06327-8 - Electro-catalytic conversion of carbon dioxide for compounds C2+ utilizing ionic liquids, BP.DD

Abstract

This project will investigate the impact of water on catalyst surfaces in ionic liquids (ILs) using in-situ infra-red spectroscopy. Over recent decades, anthropogenic rising in CO2 levels in Earth's atmosphere, now at approximately 420 ppm, have stimulated interest in electrocatalysis as a method for CO2 transformation under ambient conditions. Aqueous electrolytes, however, have limited limit electrochemical stability windows (ESW) due to the hydrogen evolution reaction (HER) at negative potentials and the oxygen evolution reaction (OER) at positive potentials. ILs, as room temperature molten salts, bypass this issue, stabilizing intermediates and extending the ESW. Imidazolium-based ILs, such as those based on BMIM+ and EMIM+, show promise, with studies demonstrating enhanced stabilization of CO2- radicals in EMIM-BF4/water mixtures. When using Cu electrodes, adsorbed CO (COad) facilitate C-C coupling, yielding C2+ molecules. This can be enhanced with different IL cations that stabilize surfaces or modify properties with water. This project employs methyltributylphosphonium bis(trifluoromethylsulfonyl)imide (P1444TFSI) to study CO2RR enhancement with two water concentrations (300 and 1200 ppm), aiming to explore their effects on the electrode/electrolyte interface. By using IR spectroscopy, particularly attenuated total reflectance (ATR-IR), insights into intermediate formation and CO2RR mechanisms will be gained, helping to deep understand how to modulate and facilitate more valuable products.