化学镀制备Ni包覆SiC核壳纳米颗粒及其介电响应  

Preparation and dielectric enhancement of nickel-coatedβ-SiC nanoparticles

作　　者：邹桂真[1] 曹茂盛[1,2] 康玉清 张亮[1] 宿辉[2] 王正平 

机构地区：[1]北京理工大学材料科学与工程学院,北京100081 [2]哈尔滨工程大学材料科学与工程系,哈尔滨150001

出　　处：《中国科技论文在线》2007年第5期330-335,共6页

基　　金：科技部863资助课题(2002AA305509);国家自然科学基金;教育部博士点基金(2004007021);黑龙江省自然科学基金(E2004-20)

摘　　要：采用简单的化学镀方法,在相对低的温度下制备了具有核-壳结构的SiC-Ni纳米复合颗粒。XRD和TEM分析结果表明,纳米Ni晶吸附在SiC颗粒表面,可以形成一层连续且致密的Ni包覆层。基于化学镀和催化理论,初步分析了化学镀核壳结构形成机理。利用波导法研究了纳米SiC颗粒和复合颗粒在8～12 GHz的微波介电特性。研究结果表明,复合颗粒的介电常数实部(ε′)和介电损耗角正切值(tanδ=ε″/ε′)都明显增强,并给出相应的理论模型。A nanoscale core-shell structure ofβ-SiCp-Ni has been prepared at lower temperature by a simple and convenient electroless plating approach.The core-shell nanoparticles have been characterized by means of XRD and TEM.The results show thatβ-SiC nanoparticles （β-SiCP） are coated by a uniform and continuous nickel shell.The mechanism based on the theory of electroless plating and palladium catalysis has been discussed in details about core-shell structure ofβ-SiCP-Ni.Dielectric permittivities of the original silicon carbide nanoparticles （β-SiCP） and nickel-coatedβ-SiCP in paraffin wax are measured respectively in the GHz frequency range from 8 to 12 GHz.The real part and dielectric loss tangent of the nickel-coatedβ-SiCP are significantly enhanced.The origin of the enhancement is theoretically discussed,and also explained by the change of surface electrical conduction behavior ofβ-SiCP and nickel-coatedβ-SiCP.

关 键 词：SiC-Ni核壳结构 化学镀 SIC 介电性能 

分 类 号：TB383.1[一般工业技术—材料科学与工程]