纳米(NH_4)_3PMo_6W_6O_(40)的室温固相合成及形成机理  

Preparation and Formation Mechanism of the (NH_4)_3PMo_6W_6O_(40) Nanopartic les by Solid State Reaction at Room Temperature

作　　者：周立群[1] 柳士忠[1] 余国锋[2] 孙聚堂[3] 

机构地区：[1]湖北大学化学与材料科学学院,武汉430062 [2]孝感学院化学系,孝感432100 [3]武汉大学化学与分子科学学院,武汉430072

出　　处：《物理化学学报》2003年第8期733-736,共4页Acta Physico-Chimica Sinica

基　　金：湖北省教育厅重大科研项目(2000Z01009);湖北省教育厅重点项目(2003A009);湖北大学重点研究项目(A0020)~~

摘　　要：以H3PMo6W6O40·23H2O和(NH4)2C2O4·H2O为原料,采用室温固相反应合成出(NH4)3PMo6W6O40·6H2O产物,用元素分析、IR、UV-Vis、XRD、TEM、TG-DTA、BET等手段确定其组成、结构和性能.结果表明,产物为纳米粒子,平均粒径为10nm.纳米粒子保持着杂多阴离子的Keggin特征结构,比表面积为167.6m2·g-1,且在465℃以下具有良好的热稳定性.反应中反应热能、结晶水和生成物H2C2O4·2H2O对形成小粒径的(NH4)3PMo6W6O40纳米粒子起关键作用.(NH4)(3)PMo6W6O40 nanoparticles were synthesized by the solid state reaction of H3PMo6W6O40.23H(2)O with (NH4)(2)C2O4.H2O at room temperature. Its structure, particle size and appearance were characterized with elemental analysis, IR, UV-Vis, XRD, TEM, TG-DTA and BET techniques. The results show that (NH4)(3)PMo6W6O40 nanoparticles are found to exhibit Keggin structure, have a surface area of 167.6 m(2).g(-1), below 465degreesC, the nanoparticles have a higher thermal stability, the mean grain size is of the value of 10 nm. In this solid state reaction, grinding and reaction thermal energy can accelerate the speed of reactant diffusion and product nucleation and decrease the particle's size, water of crystallization of reactants and product H2C2O4.2H(2)O play a key role of forming the small size (NH4)(3)PMo6W6O40 nanoparticles.

关 键 词：纳米粒子 多金属氧酸盐 笼形结构 表征 (NH4)3PMo6W6O40 室温固相合成 形成机理 催化剂 

分 类 号：O611.4[理学—无机化学]