复合γ-Fe_2O_3/M(M=Pt/Pd)纳米磁敏催化剂超声制备与表征  

Ultrasonic Synthesis and Characterization of γ-Fe_2O_3/M(M=Pt, Pd) Nanocomposites for Magnetosensitive Catalyst

作　　者：贺全国[1] 刘军[1] 胡蓉[1] 

机构地区：[1]湖南工业大学绿色包装与生物纳米技术应用湖南省重点实验室,湖南株洲412007

出　　处：《稀有金属材料与工程》2014年第6期1417-1422,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(61102031;61001053);湖南省自科基金(11JJ6038;10JJ4010;11JJ5042)

摘　　要：采用焙烧法制备γ-Fe2O3之后,再利用3-氨丙基三乙氧基硅烷(APTES)对其表面进行功能化修饰,在其溶液体系中加入氯铂酸/氯化钯溶液,使游离的四价铂粒子/二价的钯离子吸附在磁性纳米粒子表面,与氨基化基团形成配位化合物,在超声化学作用下,利用水合肼将铂离子和钯离子还原为单质,制成γ-Fe2O3/M(M=Pt/Pd)复合磁敏催化剂纳米粒子。并采用Bruker Advanced-D8粉末衍射仪,带有选区电子衍射(SAED)的透射电子显微镜(TEM),高分辨透射电子显微镜(HRTEM)和带有超导量子干涉装置(SQUID)功能的磁性测量系统(MPMS)等对γ-Fe2O3粒子和γ-Fe2O3/M复合粒子磁性进行表征。结果表明:采用焙烧法制备的γ-Fe2O3磁性纳米粒子粒径在20 nm左右,制备的γ-Fe2O3/Pt和γ-Fe2O3/Pd复合粒子粒径分别在68和36 nm左右,室温下的磁化强度分别为29.4和31.2(A·m2)/kg,磁响应性能优越,可用于磁敏催化剂反应体系。这为贵金属Pt、Pd催化剂的回收与磁敏催化剂应用提供了新的思路。The surfaces of maghemite nanoparticles prepared from magnetite by calcination process, were modified by 3-triethoxysilylpropylamine （APTES）. The chloroplatinic acid/palladium chloride was added into APTES-maghemite NPs solution, and accordingly, the pt^4＋/pd^2＋ was absorbed on the surface and formed a coordinated compound with amino groups. Finally, the complexed pt^4＋/pd^2＋ was reduced by hydrazine hydrate （HHA） to generate magnetic γ-Fe2O3/M （M=Pt/Pd） nanocomposites under ultrasonic application. The morphology, microstructure, composition and magnetic properties of the γ-Fe2O3/M NPs were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM） with selected area electron diffraction （SAED）, high resolution transmission electron microscopy （HRTEM） and superconducting quantum interference device （SQUID） magnetometry. The results show that the diameters of precursor maghemite nanoparticles are about 20 nm, and those of the γ-Fe2O3/Pt and γ-Fe2O3/Pd nanoparticles are about 68 and 36 nm, respectively. Their magnetic performances have shown a saturation magnetization （Ms） of about 29.4 and 31.2 （A·m^2）/kg at room temperature, respectively. The superior magnetic response property for magnetic sensitive catalyst system will be further investigated. These kinds of nanoparticles have provided a new way for recovering of Pt and Pd catalyzer and application of magnetosensitive catalyst system.

关 键 词：Γ-FE2O3 Γ-FE2O3 Pt复合粒子 Γ-FE2O3 Pd复合粒子 超声化学 磁敏催化剂 

分 类 号：O643.36[理学—物理化学]