Porous Cu<sub>1</sub>/TiO<sub>2–<i>x</i></sub> Catalytic Binding Pocket for Near-Unity Nitrate-to-Ammonia Conversion
Liying Zhang, Wenzhe Shang, Sen Qiao, Wei Liu, Yantao Shi
Abstract
Electrocatalytic nitrate reduction reaction (NO 3 RR) provides unique opportunities to mitigate nitrate wastewater pollution and green ammonia production, yet the sluggish kinetics regarding 8e – transfer and collective activation of multiple reactants and intermediates remain a fundamental challenge. In this study, we present a cooperative catalyst design of atomically dispersed Cu 1 species embedding onto reduced anatase TiO 2– x with rich multistage pores and oxygen vacancies (POVs), affording the target POVs-Cu δ+ -TiO 2 with a multisite nature. Particularly, the oxygen vacancies and Cu 1 sites in proximity feature a conformational enzyme-mimicking nanopocket, which essentially governs the binding fit of mutative nitrogenate intermediates in the context of synergistic catalysis. The POVs-Cu δ+ -TiO 2 delivers a near-unity Faradaic efficiency (product basis 95.0%) and remarkable ammonia yield rate up to 1321.2 μmol h –1 mg cat –1 at −0.7 V vs RHE. This study underscores the surface topography engineering on reduced metal oxides and the promising synergistic effects over the NO 3 RR electrocatalysis, providing a better alternative for nitrate wastewater pollution treatment and ammonia production.