Mesoporous covalent organic framework: An active photo-catalyst for formic acid synthesis through carbon dioxide reduction under visible light

We demonstrate the photocatalytic reduction of CO2 into HCOOH using mesoporous Covalent Organic Framework (COF) as the active photocatalyst, Co(dmg)(2) as co-catalyst with Triethanolamine (TEOA) as sacrificial electron source under atmospheric pressure. Greater than 125 TON is achieved with 10 mg catalyst. The reaction cycle is dependent on the use of co-catalyst, Co(dmg)(2) and sacrificial electron donor (TEOA). The reaction does not occur in the absence of light (445 run) and can readily be controlled by light intensity alternation. We also demonstrate that a TON of 36 can be obtained with use of sunlight using the catalytic cycle. These results open the door to an entirely new class of protocol for photocatalytic reduction of CO2 using COF and Co(dmg)(2) as co-catalyst under visible light.