【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—12GHz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．更多还原

【Abstract】 A nanoscale core-shell structure ofβ-SiCp-Ni was prepared at lower temperature by a simple and convenient electroless plating approach. The core-shell nanoparticles were 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 was 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 were measured respectively in the GHz frequency range from 8 to 12GHz. The real part and dielectric loss tangent of the nickel-coatedβ-SiCp were significantly enhanced. The origin of the enhancement was discussed in theory, and also explained by discussing the change of surface electrical conduction behavior ofβ-SiCp and nickel-coatedβ-SiCp.更多还原