Functionalization of Carbon Nanotubes with Nickel Cyclam for the Electrochemical Reduction of CO2.

The exploitation of molecular catalysts for CO 2 electrolysis requires their immobilization on the cathode of the electrolyzer. As an illustration of this approach, a Ni-cyclam complex, with a cyclam derivative functionalized with a pyrene moiety, was synthesized, shown to be a selective catalyst for CO 2 electroreduction to CO and immobilized on a carbon nanotube-coated gas diffusion electrode by using a non-covalent binding strategy. The as-prepared electrode is efficient, selective, robust for electrocatalytic reduction of CO 2 to CO. Very high turnover numbers (ca. 61460) and turnover frequencies (ca. 4.27 s -1 ) were enabled by the novel electrode material in organic solvent-water mixtures saturated in CO 2 . This material provides an interesting platform for further improvement.