Lv Zengxiang, Hao Leiduan, Yao Zhibo, Li Weixiang, Robertson Alex W, Sun Zhenyu
State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Department of Physics, University of Warwick, Coventry, CV4 7AL, UK.
Adv Sci (Weinh). 2022 Nov;9(33):e2204205. doi: 10.1002/advs.202204205. Epub 2022 Oct 17.
Many challenges in the electrochemical synthesis of ammonia have been recognized with most effort focused on delineating false positives resulting from unidentified sources of nitrogen. However, the influence of oxidizing anolytes on the crossover and oxidization of ammonium during the electrolysis reaction remains unexplored. Here it is reported that the use of analytes containing halide ions (Cl and Br ) can rapidly convert the ammonium into N , which further intensifies the crossover of ammonium. Moreover, the extent of migration and oxidation of ammonium is found to be closely associated with external factors, such as applied potentials and the concentration of Cl . These findings demonstrate the profound impact of oxidizing anolytes on the electrochemical synthesis of ammonia. Based on these results, many prior reported ammonia yield rates are calibrated. This work emphasizes the significance of avoiding selection of anolytes that can oxidize ammonium, which is believed to promote further progress in electrochemical nitrogen fixation.
电化学合成氨面临诸多挑战,目前大部分工作集中于识别由不明氮源导致的假阳性结果。然而,在电解反应过程中,氧化性阳极电解液对铵离子的交叉渗透和氧化作用的影响仍未得到探索。本文报道,使用含有卤离子(Cl和Br)的分析物可迅速将铵离子转化为N₂,这进一步加剧了铵离子的交叉渗透。此外,发现铵离子的迁移和氧化程度与外部因素密切相关,如施加的电位和Cl⁻的浓度。这些发现证明了氧化性阳极电解液对电化学合成氨具有深远影响。基于这些结果,许多先前报道的氨产率得到了校准。这项工作强调了避免选择能够氧化铵离子的阳极电解液的重要性,这被认为有助于推动电化学固氮的进一步发展。