Highly efficient electrocatalytic CO2 reduction over pyrolysis–free conjugated metallophthalocyanine networks in full pH range

Abstract

Herein, we report the first work on pyrolysis–free synthesis of robust conjugated metallophthalocyanine–based covalent triazine frameworks (MPc–CTF, M= Co, Ni) for pH-universal electrocatalytic CO2 reduction reaction (CO2RR). CoPc–CTF shows high CO Faradaic efficiency over 94%, and long-term stability over 10 h in full pH range, and industry level CO partial current densities of 378.8 mA cm−2, 165.9 mA cm−2, 172.5 mA cm−2 in alkaline, neutral and acidic electrolytes, respectively. Particularly, the CO2 utilization efficiency reaches 51.3% in acidic electrolytes. Moreover, operando characterizations and density functional theory calculations indicate the promoting effect of triazine moiety in CoPc–CTF to accelerate the formation of *COOH intermediates during CO2RR. This work provides an encouraging direction for designing robust conjugated network supported single site catalysts to access high product selectivity and high carbon utilization efficiency in electrocatalytic CO2 reduction reaction.