Emerging electrocatalytic conversion of NOx species into value-added nitrogenous chemicals

Abstract

Excessive nitrogen oxides (NOx) species such as NO, NO2, NO3– and NO2– are anthropogenically emitted from various human activities such as fossil fuel combustion, vehicle exhaust, agricultural over-fertilization and industrial wastewater, which drastically disrupts the balance of nitrogen cycle as well as poses great threats to natural environment and human health. Renewable energy-driven electrocatalytic co-reduction of NOx and abundant carbon sources has emerged as a greatly promising and sustainable strategy for the production of value-added chemicals in the decarbonized and energy-efficient route, simultaneously mitigating NOx pollution. In this review, we systematically summarize the recent advances in the conversion of NOx species into value-added nitrogenous chemicals, covering the aspects including critical adsorbed-intermediates, underlying reaction pathways and multidimensional structure-activity relationships in NOx reduction reaction and C−N coupling reaction. Furthermore, the viable upstream-electrolysis-downstream cascade systematic integrations with economic assessment are highly emphasized. Finally, a series of remaining challenges and propose insightful perspectives for the future development of this exciting direction are also highlighted. It is expected that this critical review offers valuable guidance and gives tremendous impetus for the sustainable, economical, large-scale electrified production of diverse value-added nitrogenous chemicals from NOx species.