An impactful approach for visible photocatalytic reduction of CO2 accelerated with Schiff base-cobalt complex.

To alleviate the global warming, it is necessary to transform carbon dioxide (CO2) into carbon monoxide (CO) through an expedient and resultful approach. In this work, a novel kind of Schiff base-cobalt ion complexes (CHE-Co) was constructed with 5-chorosalicylaldehyde, acetylglycine, acetic anhydride and CoCl3·6H2O as raw materials. It was discovered that CHE-Co exhibits outstanding photocatalytic activity to reduce CO2 to CO (selectivity: 91%) in an H2O/CH3CN solution (V:V = 1:4) under the irradiation of a LED-simulated solar lamp (λ > 400 nm, 90 mW cm–2). Under the optimized conditions, the yield of CO photo-catalytically reduced from CO2 can reach 15.92 μmol, with TON value of 1592 and TOF value of 159.2 h−1. The photo-catalytic mechanism of CHE-Co was proposed that CHE-Co with a positive Eonset can drive electrons shift from excited-state photosensitizer [Ru(phen)3]2+* to CHE-Co via a single-molecule rate control reaction. [ABSTRACT FROM AUTHOR]