In situ FTIR study of 2D-carbon materials for CO2 splitting under non-thermal plasma environment - selective CO production

Carbon dioxide conversion has been considered a promising solution to global warming and the storage of renewable energy as a source of CO. However, it is challenging to develop a process that combines complete conversion from one oxidant (CO2) to another - O-2. In this study, CO2 splitting has been investigated and monitored in situ, by using the plasma generated in a glow discharge reactor packed with carbonaceous materials. The results presented in the form of 2D-carbon surface FTIR spectra indicate that materials play here at least a double role as: (i) a solid adsorbent and (ii) an oxygen scavenger, shifting the overall reaction equilibrium to CO - the product side. It was proved that excited surface CO2 species are present as active intermediates. Their origin is not only the transformation from physically adsorbed molecules but also from C=O and C-O surface oxides formed through the Boudouard reaction. Microscopic and Raman spectroscopy investigations confirm this statement.