Interfacial Electronic Interactions Induced by Self‐Assembled Amorphous RuCo Bimetallenes/MXene Heterostructures for Nitrate Electroreduction to Ammonia

Abstract Electrocatalytic nitrate reduction to ammonia (NO ₃ RR) is an attractive green route to generate valuable ammonia and remove nitrates in industrial processes. However, under the intense competition of hydrogen evolution reactions (HER), it is a key challenge to improve the selectivity and reduce the energy consumption of the nitrate reduction reaction. Herein, a unique amorphous RuCo Bimetallenes confined on Ti ₃ C ₂ T _x ‐MXene (RuCo/Ti ₃ C ₂ T _x ) is reported as a highly efficient NO ₃ RR catalyst, showing a remarkable Faradaic efficiency for ammonia of 94.7% at −0.2 V versus reversible hydrogen electrode (RHE), with the corresponding high ammonia yield rate of 98.8 mg h ⁻¹ mg _cat ⁻¹ at −0.6 V versus RHE. Significantly, the RuCo/Ti ₃ C ₂ T _x heterostructures are able to operate stably at 1 A cm ⁻² for over 100 h under membrane electrode assembly (MEA) conditions with a stabilized NH ₃ Faraday efficiency. In‐depth theoretical and operando spectroscopic investigations unveil that the in situ generation of heterojunction via interfacial Ru/Co─O bridges can induce charge redistribution through Ru/Co─O‐Ti structure and modulate the electronic structure of RuCo Bimetallenes, significantly promoting ^* H production and the adsorption and activation of reactants/intermediates, while suppressing HER, thereby boosting NO ₃ RR performance. This study offers a new insight the metal‐support interaction for the development of high‐performance electrocatalysts.