Electrochemical conversion of carbon dioxide to formic acid at Sn and BDD cathodes

Electrochemical reduction of CO2 to useful compounds in the aqueous electrolyte has been actively investigated as alternative technologies to contribute to curbing the rising levels of CO2 in the atmosphere. Many researchers have focused on the CO2 reduction to formic acid, which is considered one of the main target-products owing to its usefulness for agriculture, chemical and pharmaceutical industry, and it is expected to be a good hydrogen storage medium for an upcoming H2-energy-based society [1,2]. In the last few years, an increasing attention was devoted to the utilization of tin electrode for its low cost, low toxicity as well as the high selectivity towards the synthesis of formic acid [2]. Recently, it was shown that boron-doped diamond (BDD) used as working electrode could be a promising material for the production of formic acid by CO2 reduction characterized by high stability and high faradic efficiency at low current density. In this work, the electrochemical conversion of CO2 in water solution using both tin and BDD cathode was systematically investigated to compare the performances achieved at these two electrodes. [1] M. Tomisaki, K. Natsui, N. Ikemiya, K. Nakata, and Y. Einaga, ChemistrySelect, 2018, 3.36, 10209-10213. [2] O. Scialdone, A. Galia, G. Lo Nero, F. Proietto, S. Sabatino, and B. Schiavo, Electrochimica Acta, 2016, 199, 332-341.