Insights on the C2 and C3 electroconversion in alkaline medium on Rh/C catalyst: in situ FTIR spectroscopic and chromatographic studies

• Carbon-supported Rhodium catalyst synthesis by Bromide Anion Exchange (BAE) method. • CO oxidation on Rh/C starts with linearly adsorbed (CO L ) oxidation at 0.35 V vs. RHE. • Ethanol Oxidation Reaction (EOR) on Rh/C facilitates the C 1 products selectivity. • Glycerol Oxidation Reaction (GOR) with preferential glycerate ion formation. The present work evaluates ethanol and glycerol electro-oxidation on Rh/C catalysts prepared using the Bromide Anion Exchange (BAE) method. Physicochemical characterizations were performed using Thermogravimetric Analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The SPAIRS investigations revealed that the CO adsorption modes on Rh sites occur on the linearly adsorbed CO (CO L ) and bridged bonded (CO B ) modes. In ethanol oxidation reaction (EOR), the Rh effect was evaluated by analyzing the products generated after bulk electrolysis using High-Performance Liquid Chromatography (HPLC) and in situ FTIR spectroscopy. The results confirmed the C-C cleavage Rh ability at low potentials and revealed that EOR follows both reaction pathways on Rh/C. While in glycerol oxidation reaction (GOR), Rh addition increases high added-value products formation such as glycerate ion. The GOR main route follows the glyceraldehyde pathway. The results highlighted that Rh is a good candidate for ethanol and glycerol electrochemical conversion at low potentials.