Enhancing the performance of cobalt porphyrin-based electrocatalysts for CO₂ reduction

The rise in global atmospheric carbon dioxide concentration since the beginning of the industrial era has been found an 'extremely likely' cause of the observed warming of our climate system since the mid-20th century. Concerted efforts among nations to lower CO₂ emissions can help avert a crisis, but a possible stronger response is reversing the process through technology that efficiently catalyzes CO₂ electroreduction. Carbon-supported first row transition metal complexes drive the reduction of CO₂ with remarkable activity and selectivity; however, their durability is quite low and the mechanisms behind the catalysts’ deactivation are still unclear.
This talk will focus on a group of cobalt porphyrins, and using calculations at different rungs of hybrid many-electron wave function and density-functional theory, we discuss the relationship between structure, charge and spin states, as well as differences among theoretical methods in describing the binding of CO₂, and even in determining their electronic ground states. Mechanisms of both CO₂ electroreduction and catalyst destruction are unveiled by benchmarking our theoretical predictions against data from electrochemical and spectral methods.