不同晶型和形貌MnO_2纳米材料的可控制备  

Controlled Synthesis of Manganese Oxide Nanocomposites with Different Structures and Morphologies

作　　者：许乃才[1] 马向荣[1] 乔山峰[1] 袁佳琦[1] 刘宗怀[1] 

机构地区：[1]应用表面与胶体化学教育部重点实验室陕西师范大学化学与材料科学学院,西安710062

出　　处：《化学学报》2009年第22期2566-2572,共7页Acta Chimica Sinica

基　　金：国家高技术发展研究计划(No.2007AA03Z248);陕西省自然科学基金项目(No.2007B15)

摘　　要：以KMnO4为锰源,采用水热技术在180℃条件下于不同种类酸溶液中可控制备了α-,β-,δ-MnO2,系统研究了K+,H+及阴离子对制备产物MnO2晶型和形貌的影响.研究结果表明,K+与H+在反应体系中对于制备产物晶相的生成形成竞争性影响,其量的大小对制备产物晶型具有控制作用,高浓度K+离子有助于生成α-MnO2,而高浓度的H+有利于生成β-MnO2;阴离子的种类和浓度对制备产物MnO2的晶型和形貌无显著影响.在对制备产物进行XRD,SEM和元素分析的基础上,提出了不同晶型和形貌MnO2的可能形成机理.Manganese oxides with α-, β- and δ-type structures were controllably synthesized by hydrothermally treating KMnO4 in different acid solutions at 180 ℃. The effects of metallic cations, H^＋ and anions in the reaction system on the structures and morphologies of manganese oxide nanocomposites were investigated systematically. The experimental results indicated that cations played a major role in the formation of manganese oxide nanocomposites with different structures, and K^＋ ions were in competition with H＋ ions in the solution for the formation of manganese oxide nanocomposites, α-MnO2 was formed when the amount of K^＋ ions was higher than that of H^＋ ions, while the higher amount of H^＋ ions was favorable for the formation of β-MnO2. On the other hand, both the type and the concentration of anions in the solution have no significant effect on the structure and morphology of manganese oxide nanocomposites. The possible forma- tion mechanism was proposed on the basis of the characterization for the obtained manganese oxide nanocomposites by XRD, SEM and elemental analysis.

关 键 词：水热法 MnO2晶型 形貌 形成机理 可控制备 

分 类 号：TB383.1[一般工业技术—材料科学与工程]