Carbon-based electrocatalysts for CO2 electroreduction produced via MOF, biomass, and other precursors carbonization: A review

The recycling of carbon dioxide via its electroreduction (CO2RR) is a key factor to stimulate the capture of this greenhouse gas, being a promising green strategy for achieving sustainable development. Nanostructured carbon materials play a protagonist role in the search of efficient and selective CO2RR electrocatalysts and, at the same time, pyrolysis is one of the most versatile tools to produce tailored nanocarbons. Nanocarbons involving a variety of dopants, metal single-atom sites/nanoparticles and textural/structural arrangements can be obtained through rational precursor/s selection and control of the carbonization conditions. Thus, this review aims to highlight the advances in CO2RR electrocatalysis using nanocarbons derived from MOFs, biomass, polymers, and other precursors, assessing the aspects to improve as well. Bearing in mind that selectivity toward valuable products is the ever-present obstacle, we summarize the nature and proportion of the produced compounds. With this, we provide a useful guide in which carbon synthetic conditions, structural features and electrocatalytic metrics are correlated to facilitate further progress in this boisterous field. After all, the main limitations detected in CO2RR research as well as potential approaches to address them are included.