Rationally Designed Carbon-Based Catalysts for Electrochemical C-N Coupling

The electrochemical C-N coupling process, facilitating the production of organic nitrogen substances (such as urea, methylamine, formamide, and ethylamine) via the simultaneous reduction of carbon dioxide (CO2) and small nitrogen-based substances, stands at the forefront of advancing carbon neutrality and the artificial nitrogen cycle. This method has garnered substantial interest due to its potential economic and environmental benefits. Although considerable progress has been achieved in this emerging field, it still faces challenges, including slow reactant adsorption, competing side reactions, and complex multi-step pathways, resulting in low yields and selectivity. Strategically designing and developing low-cost and exceptionally performant catalysts is crucial for cost-effective and precise electrochemical C─N bonding. This article offers an in-depth review of the electrosynthesis of valuable organic nitrogen compounds at ambient conditions from earth-abundant resources/wastes, such as CO2 and small nitrogenous molecules (nitrogen: N2, nitrite: NO2−, nitrate: NO3−, ammonia: NH3, etc.), via electrochemical C─N bond formation reactions, especially using carbon-based catalysts. The relevant electrochemical C─N bond formation mechanisms, the design principles of advanced carbon-based electrocatalysts, and the impact of different electrolyser designs are discussed, along with the present obstacles and upcoming prospects in this dynamic field.