锰负载量对活性炭载锰氧化物的结构及催化分解臭氧性能的影响(英文)  

The effects of Mn loading on the structure and ozone decomposition activity of MnO_x supported on activated carbon

作　　者：王鸣晓[1] 张彭义[1] 李金格[1] 姜传佳[1] 

机构地区：[1]清华大学环境学院环境模拟与污染控制国家重点联合实验室,北京100084

出　　处：《催化学报》2014年第3期335-341,共7页

基　　金：supported by the National High Technology Research and Development Program of China (863 Program,2012AA062701);the National Natural Science Foundation of China (21221004)~~

摘　　要：将高锰酸钾与活性炭（AC）原位氧化还原制备的活性炭载锰氧化物（MnOx/AC）用作臭氧分解的催化剂.采用扫描电镜、X射线光电子能谱、X射线衍射、电子自旋共振波谱、拉曼光谱以及程序升温还原研究了设计Mn负载量对负载锰氧化物性质（形貌、氧化态和晶体结构）的影响.结果表明, Mn负载量由0.44%增至11%,负载锰氧化物在活性炭表面由疏松的地衣状变为堆叠的纳米球状体,负载层的厚度由-180 nm增加至-710 nm,结构由氧化态＋2.9到＋3.1的低结晶β-MnOOH生长为由氧化态＋3.7到＋3.8的δ-MnO2结晶. MnOx/AC室温催化分解低浓度臭氧的活性与负载锰氧化物的形貌及含量密切相关. Mn负载量为1.1%的MnOx/AC具有疏松的地衣状形貌,催化分解臭氧的性能最高, Mn负载量为11%的MnOx/AC具有紧密的堆积结构,因而表现出最低的催化臭氧分解活性.Manganese oxide catalysts supported on activated carbon （AC, MnOx/AC） for ozone decomposition were prepared by in situ reduction of the permanganate. The morphology, oxidation state, and crystal phase of the supported manganese oxide were characterized by scanning electron micros-copy, X-ray photoelectron spectroscopy, X-ray diffraction, electron spin resonance, Raman spec-troscopy, and temperature-programmed reduction. The supported MnOx layer was distributed on the surface of AC with a morphology that changed from a porous lichen-like structure to stacked nanospheres, and the thickness of the MnOx layer increased from 180 nm to 710 nm when the Mn loading was increased from 0.44% to 11%. The crystal phase changed from poorly crystallineβ-MnOOH to δ-MnO2 with the oxidation state of Mn increasing from ＋2.9-＋3.1 to ＋3.7-＋3.8. The activity for the decomposition of low concentration ozone at room temperature was related to the morphology and loading of the supported MnOx. The 1.1%MnOx/AC showed the best performance, which was due to its porous lichen-like structure and relatively high Mn loading, while 11%MnOx/AC with the thickest MnOx layer had the lowest activity owning to its compact morphol-ogy.

关 键 词：锰氧化物 臭氧分解 活性炭 室内空气 纳米材料 

分 类 号：O643.36[理学—物理化学]