Carbon dioxide and nitrogen reduction reactions using 2D transition metal dichalcogenide (TMDC) and carbide/nitride (MXene) catalysts

Abstract

Improving the carbon dioxide and nitrogen reduction reactions (CO₂RR and NRR) can reduce anthropogenic greenhouse gas emissions while selectively producing chemicals needed for the fuel, plastic, and chemical industries. Efficient CO₂RR can be used to replace fossil fuels as well as repurpose captured CO₂, while new NRR pathways can be used to supplement or replace the energy intensive Haber–Bosch process for NH₃ generation with no CO₂ emissions. Therefore, this review article focuses on (photo)electrocatalytic and photocatalytic conversion of CO₂ and N₂ molecules into useful products, such as carbon monoxide, methanol, formic acid, and ammonia, using 2D transition metal dichalcogenides (TMDCs) and metal carbides/nitrides (MXenes). These highly tunable 2D catalysts will be evaluated for their ability to selectively and efficiently undergo CO₂RR and NRR by controlling defects, phases, edge sites, interfaces, and functional groups. We first address the CO₂RR and NRR challenges, with a particular focus on theoretical mechanisms and minimum energy pathways. We follow this discussion with a detailed review of state-of-the-art 2D TMDC and MXene experimental catalysts for CO₂RR and NRR (photo)electrocatalytic and photocatalytic reactions, and then address areas of opportunity for these catalytic reactions.