Feng Zixuan, He Yuexuan, Cui Yuhuan, Qu Yanbin, Ding Guopeng, Chen Xue, Sui Chunyu, Wei Qianling, Wang Zhili, Jiang Qing
Key Laboratory of Automobile Materials, Ministry of Education, and School of Materials Science and Engineering, Jilin University, Changchun 130022, China.
College of Chemistry and Materials Science, Hebei University, Baoding 071002, China.
Nano Lett. 2024 Sep 25;24(38):11929-11936. doi: 10.1021/acs.nanolett.4c03218. Epub 2024 Sep 12.
Electrocatalytic nitrate (NO) reduction reaction (NORR) represents a promising strategy for both wastewater treatment and ammonia (NH) synthesis. However, it is difficult to achieve efficient NORR on a single-component catalyst due to NORR involving multiple reaction steps that rely on distinct catalyst properties. Here we report a facile alloying/dealloying-driven phase-separation strategy to construct a bimodal nanoporous Ag/Ag-Co tandem catalyst that exhibits a remarkable NORR performance in a broad NO concentration range from 5 to 500 mM. In 10 and 50 mM NO electrolytes, the NH yield rates reach 3.4 and 25.1 mg h mg with corresponding NH Faradaic efficiencies of 94.0% and 97.1%, respectively, outperforming most of the reported catalysts under the same NO concentration. The experimental results and density functional theory calculations demonstrate that Ag ligaments preferentially reduce NO to NO, while bimetallic Ag-Co ligaments catalyze the reduction of NO to NH.
电催化硝酸盐（NO）还原反应（NORR）对于废水处理和氨（NH₃）合成而言都是一种很有前景的策略。然而，由于NORR涉及多个依赖不同催化剂特性的反应步骤，因此在单组分催化剂上实现高效NORR很困难。在此，我们报道了一种简便的合金化/脱合金驱动相分离策略，以构建一种双峰纳米多孔Ag/Ag-Co串联催化剂，该催化剂在5至500 mM的宽NO浓度范围内表现出卓越的NORR性能。在10 mM和50 mM NO电解质中，NH₃产率分别达到3.4和25.1 mg h⁻¹ mg⁻¹cat，相应的NH₃法拉第效率分别为94.0%和97.1%，在相同NO浓度下优于大多数已报道的催化剂。实验结果和密度泛函理论计算表明，Ag韧带优先将NO还原为NO₂，而双金属Ag-Co韧带催化NO还原为NH₃。
