Lisa EISELE1, Bletë HULAJ1, Alexey CHEREVAN2, Dominik EDER2, Katharina SCHRÖDER1
1Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria
2Institute of Materials Chemistry, TU Wien, Vienna, Austria
Photocatalytic production of carbon monoxide (CO) from CO2 has the potential for safe and atom economic production of feedstock chemicals via in-situ carbonylation chemistry. The high thermodynamic and kinetic barrier for CO2 reduction can be overcome by combining photocatalysts with ionic liquids since they can solubilize and activate large concentrations of CO2 [1]. Moreover, photocatalysts can be immobilized in ionic liquid frameworks and applied as heterogeneous catalysts in continuous processes.
To gain fundamental knowledge about the reaction mechanism we first studied the impact of various ionic liquids on photocatalyzed CO2 reduction with ruthenium(II) and rhenium(I) bipyridine complexes. Additionally, we developed novel ionic liquid-based polymeric materials applicable for reaction in gas phase, produced by radical copolymerization of the ionic liquid 1-butyl-3-vinylimidazolium chloride and photocatalytically active Re- and Ru-complexes bearing vinyl groups. The obtained copolymers were studied in the visible-light photoreduction of CO2 in solution, showing high yields and selectivity for CO formation.
[1] Lin, J., Ding, Z., Hou, Y. & Wang, X. Ionic Liquid Co-catalyzed Artificial Photosynthesis of CO. Sci. Rep. 3, 1056 (2013).