Hydroxyl-Decorated Diiron Complex as a [FeFe]-Hydrogenase Active Site Model Complex: Light-Driven Photocatalytic Activity and Heterogenization on Ethylene-Bridged Periodic Mesoporous Organosilica

Catalysts

César Jiménez-Sanchidrián¹  Juan Amaro-Gahete¹  Francisco J. Romero-Salguero¹  Dolores Esquivel¹  Haining Tian²  Mariia V. Pavliuk²  Sascha Ott² 

[1] Departamento de Química Orgánica, Edificio Marie Curie, Facultad de Ciencias, Campus Universitario de Rabanales, Instituto Universitario de Nanoquímica (IUNAN), Universidad de Córdoba, 14071 Córdoba, Spain;Ångström Laboratories, Department of Chemistry, Uppsala University, P.O. Box 523, 751 20 Uppsala, Sweden;

关键词: [FeFe]-hydrogenase;    periodic mesoporous organosilica;    biomimetic chemistry;    artificial photosynthesis;    light-driven hydrogen evolution;   

DOI  :  10.3390/catal12030254

来源: DOAJ

【 摘 要 】

A biomimetic model complex of the [FeFe]-hydrogenase active site (FeFeOH) with an ethylene bridge and a pendant hydroxyl group has been synthesized, characterized and evaluated as catalyst for the light-driven hydrogen production. The interaction of the hydroxyl group present in the complex with 3-isocyanopropyltriethoxysilane provided a carbamate triethoxysilane bearing a diiron dithiolate complex (NCOFeFe), thus becoming a potentially promising candidate for anchoring on heterogeneous supports. As a proof of concept, the NCOFeFe precursor was anchored by a grafting procedure into a periodic mesoporous organosilica with ethane bridges (EthanePMO@NCOFeFe). Both molecular and heterogenized complexes were tested as catalysts for light-driven hydrogen generation in aqueous solutions. The photocatalytic conditions were optimized for the homogenous complex by varying the reaction time, pH, amount of the catalyst or photosensitizer, photon flux, and the type of light source (light-emitting diode (LED) and Xe lamp). It was shown that the molecular FeFeOH diiron complex achieved a decent turnover number (TON) of 70 after 6 h, while NCOFeFe and EthanePMO@NCOFeFe had slightly lower activities showing TONs of 37 and 5 at 6 h, respectively.

【 授权许可】

Unknown