The local structures of silver(I) ion catalysts anchored within zeolite cavities and their photocatalytic reactivities for the elimination of N2O into N2 and O2
The local structures of silver(I) ion catalysts anchored within zeolite cavities and their photocatalytic reactivities for the elimination of N2O into N2 and O2
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DOI：
10.1021/jp0302919
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发表时间：
2004-02-19
影响因子：
3.3
通讯作者：
Anpo, M
中科院分区：
文献类型：
--
作者：
Ju, WS;Matsuoka, M;Anpo, M
Ag+/ZSM-5 催化剂通过离子交换法制备，并通过原位 XPS、XAFS（XANES 和 EXAFS）、UV-Vis、光致发光和 FT-IR 研究进行表征。发现这些 Ag+/ZSM-5 催化剂由于孤立的 Ag+ 离子而在 190 nm 左右表现出紫外吸收带。由于 N2O 吸附在 Ag+ 离子上，添加 N2O 分子导致该谱带移动至 220 nm。 N2O 在 Ag+ 离子上的吸附也可以通过 2251 cm(-1) 处特征 FT-IR 谱带的出现来阐明。在 N2O 存在下，UV 照射 Ag+/ZSM-5 催化剂，导致 N2O 在低至 298 K 的温度下光催化分解为 N-2 和 O-2。发现 200-250 nm 左右的紫外光对该反应有效，这表明孤立的 Ag+ 离子的激发在 N2O 的光催化分解中起着重要作用。
Ag+/ZSM-5 catalysts were prepared by an ion-exchange method and characterized by in-situ XPS, XAFS (XANES and EXAFS), UV-Vis, photoluminescence, and FT-IR investigations. These Ag+/ZSM-5 catalysts were found to exhibit an UV absorption band at around 190 nm due to the isolated Ag+ ions. The addition of N2O molecules leads to a shift in this band to 220 nm due to the adsorption of N2O on the Ag+ ions. The adsorption of N2O on the Ag+ ions could also be clarified by the appearance of characteristic FT-IR bands at 2251 cm(-1). UV irradiation of the Ag+/ZSM-5 catalysts in the presence of N2O led to the photocatalytic decomposition of N2O into N-2 and O-2 at temperatures as low as 298 K. It was found that UV light at around 200-250 nm is effective for the reaction, suggesting that excitation of the isolated Ag+ ion plays a significant role in the photocatalytic decomposition of N2O.