α-MnO_2纳米颗粒的可控制备及其催化性能  

Controllable Preparation and Catalytic Performance of α-MnO_2 Nanoparticles

作　　者：刘肖肖[1] 芦佳[1] 邵丽敏 吴银素[1] 马子川[1] 

机构地区：[1]河北师范大学化学与材料科学学院,河北石家庄050024 [2]河北省栾城县楼底中学,河北石家庄051430

出　　处：《河北师范大学学报（自然科学版）》2014年第3期272-277,共6页Journal of Hebei Normal University：Natural Science

基　　金：国家自然科学基金(21147004);河北省自然科学基金(B2013205100);河北师范大学重点基金(L2010Z06);河北师范大学学术科技创新项目(CG2013329355)

摘　　要：以高锰酸钾和硫代硫酸钠为前驱物,采用氧化还原沉淀法可控制备了α-MnO2纳米颗粒,并以邻二甲苯为目标污染物评价了α-MnO2纳米颗粒对其深度催化氧化性能的影响.考察了pH值、反应物的摩尔比、焙烧温度对催化剂结构和活性的影响.采用X射线衍射、扫描电子显微镜和比表面积分析仪对催化剂进行了表征.结果发现,该类α-MnO2纳米颗粒的催化活性和稳定性良好,在400~700℃保持晶型稳定,粒径为25~50nm.其中,当反应原料的反应摩尔比为8∶3、pH=5、焙烧温度400℃时所制备的催化剂可在220℃时使0.06%（体积分数）的邻二甲苯完全转化为CO2和H2O,表现出最好的催化活性,并且其活性在连续60h的测试中保持稳定.α-MnO2nanoparticles were prepared by using redox-precipitation reaction method,in which the KMnO4 and Na2S2O3 were used as the precursors.The paper inspected the reaction mechanism of α-MnO2on catalytic combution o-xylene.Effects of pH,molar ratio of reactants,and calcination temperature on its catalytic activity were investigated.The X-ray diffraction（XRD）,brunauer emmett teller（BET）, scanning electron microscope（SEM）were used to characterize these catalysts.The results found that theα-MnO2nanoparticles showed good thermal stability and good catalytic activity.The catalyst keep stable crystal shape from 400to 700℃and its particle size is between 25to 50nm.Among them,α-MnO2nanoparticles which were prepared at the condition of the raw materials for reaction molar ratio is 8∶3,pH=5,and calcination temperature is 400℃,can make 0.06%o-xylene completely transformed into water and carbon dioxide at 220℃,and showed the best catalytic activity.The catalyst remained stable after a continuous activity test 60h.

关 键 词：α-MnO2纳米颗粒 邻二甲苯 深度催化氧化 

分 类 号：O614.711[理学—无机化学]