Recent attention aroused by the reduction of carbon dioxide has as main objective the production of useful products - the “solar fuels” - in which solar energy would be stored. One route to this goal consists in first converting sunlight energy into electricity, then used to reduce CO
2 electrochemically. Conversion of carbon dioxide into carbon monoxide is thus a key-step through the classical dihydrogen-reductive Fischer-Tropsch chemistry. We will describe our work in this field using variously substituted iron tetraphenylporphyrin derivatives, that prove to be the most efficient molecular catalysts of the reduction of CO
2 to CO when generated electrochemical at the Fe(0) oxidation state, both in terms of selectivity, durability, overpotential and turnover frequency. These catalysts are remarkably active not only in organic solvent (e.g. DMF) but also in pure water at pH 7. Benchmarking of the catalytic performances, through catalytic Tafel plots, leads to a fair comparison between various reported catalysts and detailed mechanisms were obtained from electrochemical studies. Going further, a complete CO
2 conversion electrochemical cell functioning in pure water was also designed. Finally, our recent work and strategy to reduce CO
2 beyond CO (for generating hydrocarbons) will be briefly presented.
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