Bimetallic Molecular Catalyst Design for Carbon Dioxide Reduction

Abstract

The core challenge in developing cost‐efficient catalysts for carbon dioxide (CO2) conversion mainly lies in controlling its complex reaction pathways. One such strategy exploits bimetallic cooperativity, which relies on the synergistic interaction between two metal centers to activate and convert the CO2 substrate. While this approach has seen an important trend in heterogeneous catalysis as a handle to control stabilities of surface intermediates, it has not often been utilized in molecular and heterogenized molecular catalytic systems. In this review, we gather general principles on how natural CO2 activating enzymes take advantage of bimetallic strategy and how phosphines, cyclams, polypyridyls, porphyrins, and cryptates‐based homo‐ and hetero‐bimetallic molecular catalysts can help understand the synergistic effect of two metal centers.

Kinetic isotope effect offers selectivity in CO2 reduction

“…To delve into the reaction mechanism and identify the intermediates involved, FTIR-SEC was carried out in a CO 2 -saturated acetonitrile solution in an OTTLE cell. While keeping the working electrode at À2.2 V vs. Fc + /Fc 0 , the FTIR-SEC results unveiled the presence of two isotope-sensitive vibrations associated with 13 CO 2 (Fig. 2B).…”

“…Substantial progress has been made in the last few years and several molecular and material catalysts have been developed for this purpose and several of these show considerable reactivity. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Reduction of CO 2 selectively to any of the several possible products poses a challenge. The 2e À /2H + reduction of CO 2 can produce either HCOOH or CO and competes with the reduction of protons to form H 2 .…”

Understanding the Interplay of the Brønsted Acidity of Catalyst Ancillary Groups and the Solution Components in Iron-porphyrin-Mediated Carbon Dioxide Reduction

“…Examples are numerous, and we recently reviewed such features . Other recent reviews and perspectives highlight important design elements, such as discrete proton donors and groups that tune electronic features of metal sites, , hydrogen bond acceptors and redox active ancillary groups, bimetallic catalyst architectures, and combinations of such ideas in “hybrid” catalyst platforms . However, there remains much to be learned about how best to choreograph the H + and e – transfer reactions that are required for high selectivity and rapid turnover of a given substrate by a coordination complex catalyst.…”

Molecular palladium catalyst enabling efficient electrochemical C–C bond cleavage within lignin model compounds

“…23 Furthermore, these molecular catalysts frequently induce disparate reaction pathways and result in enhanced catalytic performance as demonstrated in various electrocatalysis conversions. [24][25][26][27][28][29][30][31] Hence, molecular catalysts hold enormous promise for augmenting selectivity in the electrochemical cleavage of C-C bonds within lignin. Nonetheless, molecular catalysts have yet to be explored as electrocatalysts for lignin conversion.…”