Fe的掺杂对MnO_(2)纳米管结构和甲苯降解性能的影响  

Effect of Fe doping on the structure and the toluene degradation of MnO_(2) nanotube

作　　者：汪怀建[1] 刘芳彤 杨文亭[2] 喻成龙 成书帆 刘慧灵 童明思 鲁美娟[1] WANG Huai-jian;LIU Fang-tong;YANG Wen-ting;YU Cheng-long;CHENG Shu-fan;LIU Hui-ling;TONG Mingsi;LU Mei-juan(School of Land Resource and Environment,Jiangxi Agricultural University,Nanchang 330045,China;School of Agricultural Sciences,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]江西农业大学国土资源与环境学院,南昌330045 [2]江西农业大学农学院,南昌330045

出　　处：《安全与环境学报》2023年第3期891-898,共8页Journal of Safety and Environment

基　　金：国家自然科学基金项目(51508245,51808269,52160009);江西省主要学科学术和技术带头人培养计划——青年人才项目(20212BCJL23054)。

摘　　要：采用水热法合成了MnO_(2)纳米管,同时在MnO_(2)的水热合成过程中,掺杂不同含量的Fe,制备了0.6%Fe-MnO_(2)、1%Fe-MnO_(2)和5%Fe-MnO_(2)的催化剂材料,使用扫描电镜(SEM)、X射线衍射(XRD)、氮气吸附-脱附、拉曼光谱等技术对四种催化材料的形貌和结构进行了表征,并以甲苯为目标污染物对其催化活性进行了研究。结果表明,Fe的掺杂没有影响MnO_(2)纳米管的形貌和晶型,四种催化剂的形貌均为纳米管状结构,晶型均为α-MnO_(2),而比表面积、孔容和最可几孔径显著下降。四种催化剂催化氧化甲苯时,1%Fe-MnO_(2)纳米管表现出最好的甲苯低温催化性能,这可能与掺杂1%Fe改变了Mn-O化学环境,使Mn—O的键能发生了改变,引起了晶格缺陷有关。Catalytic oxidation technology is one of the most widely used for VOCs elimination because of its scientific and industrial applications.In this study,MnO_(2)nanotube and a series of Fe dopped-MnO_(2)nano-material(0.6%Fe-MnO_(2),1%Fe-MnO_(2),and 5%Fe-MnO_(2))were prepared via a hydrothermal method,and these nano-materials utilized for the 2053 mg/m~3 toluene elimination in the flow of dry air at the condition of different temperatures.The morphology and the structural properties of nano-materials were characterized by scanning electron microscope(SEM),X-ray diffraction(XRD),N2gas adsorption-desorption,and Raman spectroscopy.The characterization results indicate that the Fe ions can enter the skeleton structure of the MnO_(2)nanotube,rather than exist on the surface of the MnO_(2)nanotube as FeOxparticles.But the Fe ions doping does not affect the MnO_(2)nanotube morphology and crystal.The morphologies of these catalysts are still nanotube andα-MnO_(2)crystals are also presented.While the specific surface area,pore-volume,and the most probable pore size of the nano-materials significantly reduced after the Fe doping,and that decreased with the increase of Fe doping.For the series of Fe dopped-MnO_(2)nano-materials,their catalytic conversion activity for toluene increased with the temperature rise.The temperature of 100%toluene conversion followed the sequence:MnO_(2),1%Fe-MnO_(2)(225℃)<0.6%Fe-MnO_(2)(235℃)<5%Fe-MnO_(2)(245℃).In addition,the temperature of T90with the 1%Fe-MnO_(2)shows lower than MnO_(2)nanotube,and the CO2selectivity also follows the same sequence.This demonstrates that the 1%Fe-MnO_(2)nanotube has the best catalytic performance for toluene.For these reasons,it may be ascribed to the fact that the chemical environment of Mn—O and the bond energy between Mn—O change over the 1%Fe dopped MnO_(2)catalyst,resulting in the generation of lattice defect,promoting the formation of oxygen vacancy,which improves the catalytic activity of 1%Fe-MnO_(2)catalyst.

关 键 词：环境工程学 甲苯氧化 二氧化锰 纳米管 FE掺杂 

分 类 号：X511[环境科学与工程—环境工程]