Details

Autor(en) / Beteiligte

• Castillo, Carmen E.
• Armstrong, Jennifer
• Laurila, Elina
• Oresmaa, Larisa
• Haukka, Matti
• Chauvin, Jérôme
• Chardon-Noblat, Sylvie
• Deronzier, Alain

Titel

Electro- and Photo-driven Reduction of CO2 by a trans-(Cl)-[Os(diimine)(CO)2Cl2] Precursor Catalyst: Influence of the Diimine Substituent and Activation Mode on CO/HCOO− Selectivity

Ist Teil von

• ChemCatChem, 2016-08, Vol.8 (16), p.2667-2677

Ort / Verlag

Weinheim: Blackwell Publishing Ltd

Erscheinungsjahr

2016

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• A series of [OsII(NN)(CO)2Cl2] complexes where NN is a 2,2′‐bipyridine ligand substituted in the 4,4′ positions by H (C1), CH3 (C2), C(CH3)3 (C3), or C(O)OCH(CH3)2 (C4) has been studied as catalysts for the reduction of CO2. Electrocatalysis shows that the selectivity of the reaction can be switched toward the production of CO or HCOO− with an electron‐donating (C2, C3) or ‐withdrawing (C4) substituent, respectively. The electrocatalytic process is a result of the formation of an Os0‐bonded polymer, which was characterized by electrochemistry, UV/Visible and EPR spectroscopies. Photolysis of the complexes under CO2 in DMF+TEOA produces CO as a major product with a remarkably stable turnover frequency during 14 h of irradiation. Our results suggest that electrocatalysis and photocatalysis occur through two distinct processes, starting mainly from an OsI dimer precatalyst if the reduction is performed by an electrode and an OsI mononuclear species in case of a photoreduction process. Diimine switch: [Os(diimine)(CO)2Cl2] complexes were synthesized, characterized, and used as electro‐ and photocatalysts for CO2 reduction. Substitution of the diimine switches the selectivity of the CO2 electroreduction toward CO or HCOO−, although the photocatalysis generates CO as a major product in all cases.