Efficient and selective molecular catalyst for the CO 2 -to-CO electrochemical conversion in water

作者：Cyrille Costentin, Marc A. Robert, Jean‐Michel Savéant, Arnaud Tatin · 发表于：Proceedings of the National Academy of Sciences · 年份：2015 · DOI：10.1073/pnas.1507063112 · 被引用次数：352 · 研究领域：CO2 Reduction Techniques and Catalysts、Catalysts for Methane Reforming、Carbon dioxide utilization in catalysis

Substitution of the four paraphenyl hydrogens of iron tetraphenylporphyrin by trimethylammonio groups provides a water-soluble molecule able to catalyze the electrochemical conversion of carbon dioxide into carbon monoxide. The reaction, performed in pH-neutral water, forms quasi-exclusively carbon monoxide with very little production of hydrogen, despite partial equilibration of CO2 with carbonic acid-a low pKa acid. This selective molecular catalyst is endowed with a good stability and a high turnover frequency. On this basis, prescribed composition of CO-H2 mixtures can be obtained by adjusting the pH of the solution, optionally adding an electroinactive buffer. The development of these strategies will be greatly facilitated by the fact that one operates in water. The same applies for the association of the cathode compartment with a proton-producing anode by means of a suitable separator.