Cobalt-N4 macrocyclic complexes for heterogeneous electrocatalysis of the CO2 reduction reaction

Metal-N4 (M-N4) macrocyclic complexes are interesting electrocatalysts due to their well-defined structures and rich molecular tuning. Among them, metal phthalocyanines have been widely studied for the carbon dioxide reduction reaction (CO2RR) in heterogeneous systems demonstrated good electrocatalytic performance. However, other like corroles porphyrins much less explored, often show inferior performances. In this study, three cobalt complexes, phthalocyanine, meso-tetraphenylporphyrin, meso-triphenylcorrole (CoPc, CoTPP CoTPC) investigated electrocatalysis of CO2RR. Although CoPc/carbon nanotube (CNT) hybrid exhibits high activity, CNT hybridization does not work CoTPC that hold weak interactions with CNTs. By drop-dry method a loading 5.4 × 10–7 mol cm–2, could deliver appreciable electrode activities. Poly(4-vinylpyridine) (PVP) introduction is further as facile afford enhanced activities at low loadings through enhancing molecule-substrate interactions. The partial current density monoxide CoTPP+CNT/PVP around 8 times higher than sample without PVP –0.67 V versus reversible hydrogen electrode. This provides solutions enhance substrate systems.