Enhanced CO2 photoreduction by a graphene-porphyrin metal-organic framework under visible light irradiation

A photocatalyst consisting of a porphyrin-based metal-organic framework (Al/PMOF) and amine-functionalized graphene (NH2-rGO) has been designed to reduce CO2. The structure of the hybrid MOF is investigated as a function of weight percentage of NH2-rGO added to the Al-PMOF. Also, the graphene-based MOF significantly enhances CO2 photoreduction compared with the Al-PMOF and the porphyrin ligand. This type of photocatalyst exhibits excellent visible light-driven CO2 to formate (HCOO-) formation. The formate evolution rate on NH2-rGO (5 wt%)/Al-PMOF is 685.6 mol g(cat.)(-1) h(-1) with almost 100% selectivity in the presence of TEOA as the sacrificial agent and hydrogen source, which is the highest value compared to those reported in other studies.