Liu Ruoyu, Zhou Bing, Liu Lizhong, Zhang Yan, Chen Yu, Zhang Qiaoling, Yang Mingliang, Hu Lanping, Wang Miao, Tang Yanfeng
School of Chemistry and Chemical Engineering, Nantong University, 9, Seyuan Road, Jiangsu Province, Nantong 226019, PR China.
School of Chemistry and Chemical Engineering, Nantong University, 9, Seyuan Road, Jiangsu Province, Nantong 226019, PR China; Nantong Key Lab of Intelligent and New Energy Materials, Nantong, 226019, China.
J Colloid Interface Sci. 2021 Mar;585:302-311. doi: 10.1016/j.jcis.2020.11.096. Epub 2020 Dec 7.
Porous Mn-based mullite SmMnO was synthesized by the in-situ dismutation of solid state Mn in bulk SmMnO perovskite to catalytic oxidation of benzene and chrolobenznen. The physicochemical property of catalyst was acquired by XRD, SEM, N adsorption-desorption, XPS, O-TPD and H-TPR. Compared with that of bulk SmMnO and bulk SmMnO, the porous SmMnO mullite (SmMnO-ID) displayed higher molar ratios of Mn/Mn and O/O, and better active oxygen desorption capacity, reducibility and larger specific surface, which promoted the preferable low-temperature catalytic oxidation of VOC. The increase in the content of Mn on the surface of the Sm-Mn mullite reduced the surface defects and increased the proportion of its surface lattice oxygen, thereby promoting the attack of VOC molecules by more lattice oxygen. Combined with the analysis of reactant intermediate for benzene oxidation by in situ diffuse reflectance infrared Fourier transform spectroscopy, the catalytic mechanism of the catalyst was also explored. Moreover, SmMnO-ID also showed the excellent stability and the superior removal of mixed VOCs with different concentration ratios. This finding provides an efficient and practical method for exploiting highly active Mn-based mullite with a high efficiency and stability for the purification of air pollution.
通过块状SmMnO钙钛矿中固态Mn的原位歧化反应制备了多孔Mn基莫来石SmMnO，用于催化氧化苯和氯苯。采用XRD、SEM、N吸附-脱附、XPS、O-TPD和H-TPR等手段对催化剂的物理化学性质进行了表征。与块状SmMnO和块状SmMnO相比，多孔SmMnO莫来石（SmMnO-ID）具有更高的Mn/Mn和O/O摩尔比，以及更好的活性氧脱附能力、还原性和更大的比表面积，促进了VOC的低温催化氧化。Sm-Mn莫来石表面Mn含量的增加减少了表面缺陷，提高了表面晶格氧的比例，从而促进了更多晶格氧对VOC分子的攻击。结合原位漫反射红外傅里叶变换光谱对苯氧化反应中间体的分析，探讨了该催化剂的催化机理。此外，SmMnO-ID还表现出优异的稳定性和对不同浓度比混合VOCs的高效去除能力。这一发现为开发高效稳定的高活性Mn基莫来石用于空气污染净化提供了一种有效且实用的方法。
