Boosting electrochemical ammonia synthesis via dynamic nitrogen carriers coupled with electron-rich Lewis acidic sites on TiO2−x nanofiber

In light of the high energy consumption and substantial carbon emissions associated with traditional NH 3 production based on the Haber–Bosch process, the aqueous electrochemical nitrogen reduction reaction (NRR) offers a clean and sustainable alternative production route. Nevertheless, activating the N N bonds at room temperature is challenging due to the high bond energy, severely hindering the development and commercialization of the electrochemical NRR. Herein, we report a synergistic strategy for achieving efficient N 2 activation at ambient conditions that combines electrolyte engineering with catalytic site-modulated TiO 2−x nanofiber electrocatalysts. The synthesized TiO 2−x nanofiber electrocatalysts contained abundant intrinsic oxygen vacancies and were further modified with hydroxyl groups to create electron-rich Lewis acidic Ti sites. Additionally, BF 3 was engineered into the electrolyte microenvironment, and it could form adducts with N 2 , serving as a dynamic carrier for N 2 transport. The electron-rich Lewis acidic sites and the dynamic carriers exerted a ‘pull–pull’ effect on N 2 , thereby weakening the N N bonds. Through electrochemical performance evaluation, the designed electrocatalytic scheme achieved an NH 3 yield of ∼57.15 μg h −1 mg −1 and a Faradaic efficiency of ∼15.14 %. We anticipate that this methodology will provide new insights into the development of electrochemical ammonia synthesis, particularly in relation to multifaceted design.