Density function theoretical and experimental study of NH3 + NOx adsorptions on MnOx/TiO2 surface
Density function theoretical and experimental study of NH3 + NOx adsorptions on MnOx/TiO2 surface
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DOI：
10.1016/j.commatsci.2015.08.054
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发表时间：
2016-02
影响因子：
3.3
通讯作者：
Zhang Liangjing;S. Cui;H. Guo;Xiaoyue Ma;W. Lu
中科院分区：
文献类型：
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作者：
Zhang Liangjing;S. Cui;H. Guo;Xiaoyue Ma;W. Lu
基于密度泛函理论和氨低温选择性催化还原NOx的实验，研究了NO和NH3气体分子在Mn 3 O 4/TiO 2催化剂上的吸附行为。在90-300 °C温度范围内系统考察了共沉淀法制备的Mn 3 O 4/TiO 2催化剂的SCR性能。结果表明，氮氧化物首先吸附在锰端形成硝酸盐物种，然后NH3更倾向于吸附在Brønsted酸中心.桥连硝酸盐和双齿硝酸盐可转化为单齿硝酸盐，而水分子在催化剂表面的吸附和解离是羟基的主要来源，当有氨和水分子存在时，形成NH 4+。结果表明，L-H机理在NH3-SCR过程中起主要作用。
The adsorption of NO and NH3gaseous molecules on Mn3O4/TiO2catalysts is studied based on density function theory and the corresponding experiments for low-temperature SCR of NOxby ammonia. The SCR performances of the Mn3O4/TiO2catalysts prepared by joint precipitation method were systematically carried out in the temperature range of 90–300 °C. The results show that nitrogen oxide can first adsorb on the manganese-terminal to form nitrates species, and then NH3are more inclined to adsorb on Brønsted acid sites. Bridging nitrate and bidentate nitrate can be turned into monodentate nitrates, and NH4+was formed when there is ammonia and water molecules because the adsorption and dissociation of the water on the surface of the catalyst is the main source of hydroxyl groups. It is indicated that L-H mechanism plays a major role in NH3-SCR process.