Porous metal-porphyrin triazine-based frameworks for efficient CO2 electroreduction

Electrochemical reduction of CO2 (ECR-CO2) into high value-added products plays a crucial role in energy conversions. Herein, we developed a family of porous metal-porphyrin triazine-based frameworks (MPTFs-x, M = Mn, Fe, Co, Ni, and Cu, x = temperature) with a specific surface area up to 977 m(2) g(-1) and homogenously dispersed transition-metals. Benefiting from a high content of N species of 8.43 at.% and abundantly exposed Ni-N-x active sites, NiPTFs-600 displayed a superb Faradaic efficiency (FE) of CO production (> 90 %) in the range of -0.55 V to -0.95 V with the maximum FE of 97.6 % and current density of 10.8 mA cm(-2) at -0.8 V. The reaction mechanism was found to be the adsorption of CO2 molecules to form *CO2 intermediates, accompanied by successive protonation to produce *COOH and then *CO.