Extended Investigation of Electrochemical CO2 Reduction in Ethanolamine Solutions by SECM

The electrochemical reduction of carbon dioxide is very much in the focus of interest today. Intensive research is carried out in leading laboratories trying to work out methods for making useful materials from this unwanted greenhouse gas using solar or wind power generated excess electric energy. In this work, electrochemical reduction experiments are carried out in homemade cells supplied with different metal electrodes. Electrolytes containing carbon dioxide absorbing components like monoethanolamine (MEA) or KHCO3, KOH, and K2CO3 solutions are used. Metal-containing species were noticed in the used electrolytes after being in contact with the metal working electrodes. Therefore parallel to the electrochemical measurements, the metal components in the electrolyte were checked with atomic absorption methods for getting better insight into the nature of the electrode passivation. This paper attempts to compare the behavior of different electrode materials (copper, nickel) in CO2 capturing media, and investigate of the products of the electrolysis using Scanning Electrochemical Microscopy (SECM), Atomic Absorption Spectroscopy (AAS) and gas chromatography.