Coupling denitrification and ammonia synthesis via selective electrochemical reduction of nitric oxide over Fe2O3 nanorods

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 10; no. 12; pp. 6454 - 6462
• Main Authors: Liang, Jie, Chen, Hongyu, Mou, Ting, Zhang, Longcheng, Lin, Yiting, Luchao Yue, Luo, Yongsong, Liu, Qian, Li, Na, Abdulmohsen Ali Alshehri, Shakir, Imran, Agboola, Philips O, Wang, Yuanyuan, Tang, Bo, Ma, Dongwei, Sun, Xuping
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 22.03.2022
• Subjects: Ammonia; batteries; Catalysts; Chemical reduction; Denitrification; Density functional theory; Electrocatalysts; Electrochemistry; Electrode materials; Electron states; Ferric oxide; Gaseous wastes; Nanorods; Nitric oxide; Nitrogen cycle; value added; wastes
• ISSN: 2050-7488; 2050-7496; 2050-7496
• DOI: 10.1039/d2ta00744d

Direct electrochemical conversion of nitric oxide (NO) into ammonia (NH3) holds great promise for high value-added utilization of industrial gaseous waste and simultaneously mitigating the human-caused imbalance of the global nitrogen cycle. Here, Fe2O3 nanorods are proposed as a superb electrocatalyst for the NO reduction reaction to produce NH3 under ambient conditions. The catalyst achieves a large NH3 yield of 78.02 μmol h−1 cm−2 with a fairly high faradaic efficiency of 86.73% in neutral media. Using such a catalyst as the cathodic material, a Zn–NO battery was assembled as an NH3-producing device with excellent NO conversion efficiency, capable of delivering a power density of 1.18 mW cm−2 and an NH3 yield of 145.28 μg h−1 mgcat.−1. Density functional theory calculations suggest that NO binds to the Fe2O3 (104) surface most strongly via electronic state interaction, adopting a charge “acceptance-donation” mechanism and is significantly activated through the 2π* back-donation effect.