Robust Biological Hydrogen-Bonded Organic Framework with Post-Functionalized Rhenium(I) Sites for Efficient Heterogeneous Visible-Light-Driven CO2 Reduction

A robust 2,2 '-bipyridine (bpy)-derived biological hydrogen-bonded framework (HOF-25) has been realized depending on guanine-quadruplex with the assistance of pi-pi interaction, which reacts with Re(CO)(5)Cl to give a post-functionalized HOF-25-Re. X-ray absorption fine structure spectroscopic study on HOF-25-Re confirms the covalent attachment of Re(bpy)(CO)(3)Cl segments to this HOF. Robust and recycled HOF-25-Re bearing photocatalytic Re(bpy)(CO)(3)Cl centers displays good heterogeneous catalytic activity towards carbon dioxide photoreduction in the presence of [Ru(bpy)(3)]Cl-2 and triisopropanolamine in CH3CN under visible-light irradiation, with both high CO production rate of 1448 mu mol g(-1) h(-1) and high selectivity of 93 %. Under the same conditions, the experimental turnover number of HOF-25-Re (50) is about 8 times as that of the homogeneous control Re(bpy)(CO)(3)Cl. The sustainably regenerated HOF-25-Re via crystallization and post-modification processes shows recovered photocatalytic performance.

Automated summary

A robust biological hydrogen-bonded framework (HOF-25) derived from 2,2'-bipyridine (bpy) was utilized to covalently attach Re(bpy)(CO)(3)Cl segments, showing good heterogeneous catalytic activity for carbon dioxide photoreduction with high CO production rate and selectivity.