Efficient Nitrogen Fixation to Ammonia through Integration of Plasma Oxidation with Electrocatalytic Reduction. (11th May 2021)

• Record Type: Journal Article
• Authors: Li, Laiquan; Tang, Cheng; Cui, Xiaoyang; Zheng, Yao; Wang, Xuesi; Xu, Haolan; Zhang, Shuai; Shao, Tao; Davey, Kenneth; Qiao, Shi‐Zhang
• Is Part Of: Angewandte Chemie. Volume 133:Number 25(2021)
• Page Start: 14250
• Page End: 14256
• Publication Date: 2021-05-11
• Subjects: ammonia production -- boron-rich surface -- electrocatalytic nitrate reduction -- nitrogen fixation -- plasma; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202104394
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Present one‐step N2 fixation is impeded by tough activation of the N≡N bond and low selectivity to NH3 . Here we report fixation of N2 ‐to‐NH3 can be decoupled to a two‐step process with one problem effectively solved in each step, including: 1) facile activation of N2 to NO x − by a non‐thermal plasma technique, and 2) highly selective conversion of NO x − to NH3 by electrocatalytic reduction. Importantly, this process uses air and water as low‐cost raw materials for scalable ammonia production under ambient conditions. For NO x − reduction to NH3, we present a surface boron‐rich core–shell nickel boride electrocatalyst. The surface boron‐rich feature is the key to boosting activity, selectivity, and stability via enhanced NO x − adsorption, and suppression of hydrogen evolution and surface Ni oxidation. A significant ammonia production of 198.3 μmol cm −2 h −1 was achieved, together with nearly 100 % Faradaic efficiency. Abstract : A two‐step process, serially integrating non‐thermal plasma technique for facile N2 to NO x − and electrocatalytic reduction for highly selective conversion of NO x − to NH3, is presented. A surface boron‐rich nickel boride electrocatalyst was developed to boost the activity, selectivity, and stability for nitrate reduction to NH3 with nearly 100 % Faradaic efficiency and low overpotential.