铜包裹碳化硅颗粒复合粉体的化学原位沉积制备与表征

以铜氨离子为铜源, 水合肼为还原剂, 在表面预氧化的SiC表面, 采用一步原位化学沉积法制备了均匀包裹Cu颗粒的SiC复合粉体. 采用扫描电子显微镜(SEM)、X射线衍射(XRD)、傅立叶红外光谱(FT-IR)、Zeta电位等测试表征手段研究了工艺条件对原位沉积反应的影响. 研究发现SiC表面预氧化形成的SiO2层能显著增强对铜氨离子吸附能力, 有助于原位还原生成单质Cu, 形成近乎连续包裹层. 控制反应体系中铜氨离子浓度和反应温度可以影响反应速率, 从而控制Cu颗粒的沉积速率和包裹效果. 对比研究表明, 在0.2 mol/L铜氨离子溶液中70℃反应, 在预氧化的SiC表面能够获得最佳包裹层.

Preparation and Characterization of Cu Coated SiC Composite Powders by in-situ Chemical Deposition

A facile one-step in-situ chemical deposition method was introduced to synthesize Cu-Coated SiC composite powders,using Cu(NH3)4]2+ ions as copper source and N2H4.H2O as reductant,respectively.Scanning electronic microscope(SEM),X-Ray diffraction(XRD),Fourier transform infrared spectroscope(FT-IR) and Zeta potential were used to investigate the structure,morphology and composition of the prepared core/shell composite powders.The corresponding formation mechanism was proposed based on the comparative study.It is revealed that the SiO2 film on the surfaces of pre-oxidated SiC particles can effectively enhance the adsorption of Cu(NH3)4]2+ ions toward the negatively charged surface,which is favorable to the following in-situ reduction by N2H4.H2O around SiC particles.Nearly continuous Cu coating can be formed by changing the reaction process.The concentration of Cu(NH3)4]2+ ions and reaction temperature affect the reaction rate and coating structure.The process parameters are optimized to obtain the best coating structure with Cu(NH3)4]2+ ions concentration of 0.2 mol/L and reaction temperature of 70℃,respectively.