Unveiling the Activity Origin of Copper-based Electrocatalyst for Selective Nitrate Reduction to Ammonia.
Unveiling the Activity Origin of Copper-based Electrocatalyst for Selective Nitrate Reduction to Ammonia.
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DOI：
10.1002/ange.201915992
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发表时间：
2020-01
影响因子：
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通讯作者：
Yuting Wang;Wei Zhou;Ranran Jia;Yifu Yu;Bin Zhang
中科院分区：
文献类型：
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作者：
Yuting Wang;Wei Zhou;Ranran Jia;Yifu Yu;Bin Zhang
在反应条件下揭示催化材料的活性相对于设计用于选择性硝酸盐还原成氨的高效电催化剂非常重要。在这里，我们探讨了 CuO 在选择性硝酸盐电还原成氨时活性显着增强的根源（法拉第效率：95.8%，选择性：81.2%）。 15 N同位素标记实验证明氨来源于硝酸盐还原。采用 1 H 核磁共振 (NMR) 谱和比色法对氨进行定量。原位拉曼和异位实验表明，CuO被电化学转化为Cu/Cu 2 O，作为活性相。在线微分电化学质谱（DEMS）和密度泛函理论（DFT）计算的综合结果表明，界面处从Cu 2 O到Cu的电子转移可以促进* NOH中间体的形成并抑制析氢反应，从而具有高选择性和法拉第效率。
Unveiling the active phase of catalytic materials under reaction conditions is important for the designed construction of efficient electrocatalysts for selective nitrate reduction to ammonia. Here, we probed the origin of the prominent activity enhancement for CuO (Faradaic efficiency: 95.8%, Selectivity: 81.2%) toward selective nitrate electroreduction to ammonia. 15 N isotope labeling experiments proved that ammonia originated from nitrate reduction. Both the 1 H nuclear magnetic resonance (NMR) spectra and colorimetric methods were performed to quantify ammonia. In situ Raman and ex situ experiments revealed that CuO was electrochemically converted into Cu/Cu 2 O, which serves as an active phase. The combined results of online differential electrochemical mass spectrometry (DEMS) and density functional theory (DFT) calculations demonstrated that the electron transfer from Cu 2 O to Cu at the interface could facilitate the formation of * NOH intermediate and suppress the hydrogen evolution reaction, leading to high selectivity and Faradaic efficiency.