Photocatalytic systems developed from complexes with only abundant metals, i.e., Cu-I(dmp)(P)(2)(+) (dmp = 2,9-dimethyl-1,10-phenanthroline; P = phosphine ligand) as a redox photosensitizer and Fe-II(dmp)(2)(NCS)(2) as a catalyst, produced CO as the main product by visible light irradiation. The best photocatalysis was obtained using a Cu-I complex with a tetradentate dmp ligand tethering two phosphine groups, where the turnover number and quantum yield of CO formation were 273 and 6.7%, respectively.