Two Targets with One Shot: Cost-Efficient Electrochemical CO₂ Reduction Coupled with the Synthesis of Cu- and Zn-Based Metal–Organic Frameworks

To address the primary issue associated with electrochemical CO2 reduction reaction (eCO2RR) utilizing conventional electrolyzers such as low-energy efficiency, we present a techno-economically paired electrolyzer for eCO2RR, which is efficiently coupled with the electrochemical synthesis of Zn- or Cu-based metal–organic frameworks (MOFs) under mild conditions. The electro-oxidative generation of Zn2+ or Cu2+ in the presence of either H3BTC, H2BDC, or H2AIP (5-aminoisophthalic acid) as linker leads to the in situ formation of the respective MOFs in the anodic compartment. Conversely, the cathodic part is equipped with a high-performance hybrid electrocatalyst composed of cobalt phthalocyanine (CoPc) and homemade N-doped ionic liquid-derived ordered mesoporous carbons (GIOMC and IFMC). It was interestingly found that OMCs, regardless of whether they contained high or low nitrogen content, exhibited strong affinity for interacting with CoPc. This interaction resulted in the uniform distribution of CoPc, which is of paramount importance for achieving enhanced electrocatalytic performance. These studies indicate that the introduced hybrid catalysts (CoPc@GIOMC and CoPc@IFMC) demonstrate suitable stability and electrochemical performance, even after prolonged electrolysis periods. The MOFs prepared using both controlled potential and constant-current protocols strongly emphasize the successful integration of oxidatively generated MOFs with eCO2RR in an efficient manner. The structural analysis of the synthesized MOFs demonstrated excellent alignment with those prepared using solvothermal methods. To the best of our knowledge, this work represents the first example of utilizing the paired eCO2RR in conjunction with the simultaneous electrosynthesis of MOFs under mild and environmentally friendly conditions.