| Summary: | 碩士 === 國立清華大學 === 材料科學工程學系 === 90 === The purpose of this study is to obtain Co-Pd nano-bimetallic particles. A chemical reduction method is performed by polyol process. In the polyol process, glycol is as a reducing agent while PVP is as a protective agent. In addition, NaOH solution is added to adjust pH value and maintain at 11, and the reduction process is performed.
According to the results of ultraviolet/visible spectra, after reaction for 270 min., the nano-particles become stable. Based on TEM studies, the average size of nano-particles is 2.5 ~ 5 nm. In addition, the nano-particle possesses FCC structure, identified using selected area diffraction pattern, while the crystallinity decreases with increasing Co content. Properties of nano-particles after annealing at various temperatures were also explored. From XRD analyses, the crystallinity improves with increasing annealing temperature, but unobvious as Co content increases. And the diffraction peaks shift manifestly with different component ratios. From XRD and VSM analyses, there are new Co-Pd compounds synthesized between 25 ~ 50 at% and 55 ~ 75 at% Co.
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