Boosting electrochemical ammonia synthesis via dynamic nitrogen carriers coupled with electron-rich Lewis acidic sites on TiO nanofiber.

In light of the high energy consumption and substantial carbon emissions associated with traditional NH 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 NN 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 activation at ambient conditions that combines electrolyte engineering with catalytic site-modulated TiO nanofiber electrocatalysts. The synthesized TiO nanofiber electrocatalysts contained abundant intrinsic oxygen vacancies and were further modified with hydroxyl groups to create electron-rich Lewis acidic Ti sites. Additionally, BF was engineered into the electrolyte microenvironment, and it could form adducts with N, serving as a dynamic carrier for N transport. The electron-rich Lewis acidic sites and the dynamic carriers exerted a 'pull-pull' effect on N, thereby weakening the NN bonds. Through electrochemical performance evaluation, the designed electrocatalytic scheme achieved an NH yield of ∼57.15 μg h mg 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.