用于通过三重反应在低过电位下将硝酸盐高效电催化转化为氨的银-氧化钴-氢氧化氧钴纳米线串联催化剂。

Ag-Co O -CoOOH-Nanowires Tandem Catalyst for Efficient Electrocatalytic Conversion of Nitrate to Ammonia at Low Overpotential via Triple Reactions.

作者信息

Wu Shilu, Jiang Yingyang, Luo Wenjie, Xu Peng, Huang Longlong, Du Yiwen, Wang Hui, Zhou Xuemei, Ge Yongjie, Qian Jinjie, Nie Huagui, Yang Zhi

机构信息

Key Laboratory of Carbon Materials of Zhejiang, College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, P. R. China.

出版信息

Adv Sci (Weinh). 2023 Nov;10(33):e2303789. doi: 10.1002/advs.202303789. Epub 2023 Oct 11.

DOI:10.1002/advs.202303789

PMID:37822155

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10667848/

Abstract

The electrocatalytic conversion of nitrate (NO ‾) to NH (NO RR) offers a promising alternative to the Haber-Bosch process. However, the overall kinetic rate of NO RR is plagued by the complex proton-assisted multiple-electron transfer process. Herein, Ag/Co O /CoOOH nanowires (i-Ag/Co O NWs) tandem catalyst is designed to optimize the kinetic rate of intermediate reaction for NO RR simultaneously. The authors proved that NO ‾ ions are reduced to NO ‾ preferentially on Ag phases and then NO ‾ to NO on Co O phases. The CoOOH phases catalyze NO reduction to NH via NH OH intermediate. This unique catalyst efficiently converts NO ‾ to NH through a triple reaction with a high Faradaic efficiency (FE) of 94.3% and a high NH yield rate of 253.7 μmol h cm in 1 M KOH and 0.1 M KNO solution at -0.25 V versus RHE. The kinetic studies demonstrate that converting NH OH into NH is the rate-determining step (RDS) with an energy barrier of 0.151 eV over i-Ag/Co O NWs. Further applying i-Ag/Co O NWs as the cathode material, a novel Zn-nitrate battery exhibits a power density of 2.56 mW cm and an FE of 91.4% for NH production.

摘要

将硝酸盐（NO₃⁻）电催化转化为氨（NO₃RR）为哈伯-博施工艺提供了一种有前景的替代方法。然而，NO₃RR的整体动力学速率受到复杂的质子辅助多电子转移过程的困扰。在此，设计了Ag/Co₃O₄/CoOOH纳米线（i-Ag/Co₃O₄ NWs）串联催化剂，以同时优化NO₃RR中间反应的动力学速率。作者证明，NO₃⁻离子在Ag相上优先还原为NO₂⁻，然后在Co₃O₄相上NO₂⁻还原为NO。CoOOH相通过NH₂OH中间体催化NO还原为NH₃。这种独特的催化剂通过三步骤反应将NO₃⁻高效转化为NH₃，在1 M KOH和0.1 M KNO₃溶液中，相对于可逆氢电极（RHE）在-0.25 V时，法拉第效率（FE）高达94.3%，NH₃产率高达253.7 μmol h⁻¹ cm⁻²。动力学研究表明，将NH₂OH转化为NH₃是速率决定步骤（RDS），在i-Ag/Co₃O₄ NWs上的能垒为0.151 eV。进一步将i-Ag/Co₃O₄ NWs用作阴极材料，一种新型的硝酸锌电池表现出2.56 mW cm⁻²的功率密度和91.4%的NH₃生产法拉第效率。