(Invited) Carbon Dioxide As a Sustainable One-Carbon Precursor in Electrochemical Synthesis

Abstract

Carbon dioxide is an abundant and under-utilized feedstock in synthetic chemistry. At present, the most common one-carbon (C1) precursor is methane, which is converted to syngas via steam methane reforming under harsh conditions, for use in the synthesis of diverse chemicals, including acids, alcohols, and hydrocarbons. One strategy for developing a carbon-negative path for chemical synthesis is to replace steam methane reforming with carbon dioxide reduction to carbon monoxide, along with hydrogen evolution. These reactions can be conduced in a modular fashion through electrochemical routes powered by renewable electricity. I will present methods by which highly-dispersed metal phthalocyanine catalysts heterogenized on carbon paper supports can achieve high turnover frequencies for converting carbon dioxide to carbon monoxide at room temperature. A second strategy for utilizing CO2 as a C1 precursor involves direct carboxylation of intermediates in organic synthesis, circumventing the need to produce syngas as an intermediate. Our group has shown sustainable routes whereby carbon-halogen and carbon-nitrogen bonds can be carboxylated and elucidated the mechanism by which this transformation occurs. These methods will be discussed in the context of the diverse scales at which decarbonization of the chemical industry needs to occur to secure a sustainable paradigm for producing critical chemicals and materials.