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We present two as-synthesized Fe(II)-based molecular catalysts with 1,10-phenanthroline (phen) ligands; Fe(phen)₃Cl₂ (<b>1</b>) and [Fe(phen)₂(CH₃CH₂OH)Cl]Cl (<b>2</b>), and their robust catalytic properties for the conversion of CO₂ to CO in DMF/TEOA (DMF = <i>N</i>,<i>N</i>&#8217;-dimethylformamide; TEOA = triethanolamine) solution containing Ru(bpy)₃²⁺ and BIH (1,3-dimethyl-2-phenyl-2,3- dihydro-1<i>H</i>-benzo-[d]-imidazole). High turnover numbers (TONs) of 19,376 were achieved with turnover frequencies (TOFs) of 3.07 s^&#8722;1 for complex <b>1</b> (1.5 &#215; 10^&#8722;7 M). A quantum efficiency of 0.38% was observed after 5 h irradiated by 450 nm monochromatic light. The generation rate of CO₂ and H₂ were tuned by optimizing the experimental conditions, resulting in a high CO selectivity of 90%. The remarkable contribution of the photosensitizer to the total TON_CO was found being 19.2% (as shown by tests under similar conditions without catalysts) when BIH was employed as a sacrificial electron donor. The product selectivity in complex <b>2</b> reached 95%, and the corresponding TON_CO and TOF_CO were 33,167 and 4.61 s^&#8722;1 in the same concentration with complex <b>1</b> used as catalyst; respectively. This work provides guidance for future designs of simple, highly efficient and selective molecular catalytic systems that facilitate carbon-neutral solar-to-fuel conversion processes