微細金屬粉末由於粒徑小、表面積大，具有許多獨特的性質，以銅及銀粉為例，銀粉的導電性、導熱性優良，有良好的抗氧化及抗菌性質，但價格昂貴；而銅粉亦具有優良的導電與導熱性，但抗氧化性質差，暴露在空氣中時，表面容易形成一層氧化膜，影響其特性，惟價格低廉。因此若能在銅粉表面鍍一銀層，可克服此二種粉末的缺點，而發揮其優點。
　　本研究以市售銅粉為核種，以硫酸銀為前驅鹽，以酒石酸(TA)、葡萄糖酸鈉(SG)為螯合劑，採用逐步還原法製備核殼結構之銅/銀粉，所得之銅/銀粉以XRD、SEM及FT-IR進行性質分析。在最佳TA/Ag+及SGA/Ag+之莫爾比，銅粉表面可鍍成緊密之銀層。抗氧化分析結果證實銅粉表面之銀為連續包覆層。導電度量測顯示銀含量為10%之銅銀粉(21.73×10-3Ω．cm)與銀粉(4.85×10-3Ω．cm)的電阻係數相近。
　　抗菌性質量測係以紙錠擴散法，銅/銀粉可有效抑制大腸桿菌(ATCC 15480)與金黃色葡萄球菌(ATCC 15285)之生長，並隨銀含量的增加其抗菌效果也愈為顯著。

　　Fine metal powders have many unique properties due to their small sizes and large surfaces. Silver powders have excellent electrical conductivity, thermal conductivity, good antioxidation and antibacterial properties, but very expensive. On the other hand, copper powders have good electrical conductivity, thermal conductivity and inexpensive price. However, the poor antioxidation properties of copper prevents it from long time exposure to air, because the surface is easy to form an oxide layer and change the conductivity. If a silver layer can be coated on the copper powder, the shortcomings of these two powders, if used individually, can be overcome.
　　In this study, commercial copper powders were used as the nuclei, silver sulfate was used as the precursor salt, tartaric acid (TA) and sodium gluconate acid(SG) as chelating agent and core-shell structured Cu/Ag particles were synthesized by successive reduction process. The synthesized Cu/Ag powders were characterized using XRD, SEM and FT-IR. Ag can be formed as a dense layer coated on the surface of Cu powders at a proper molar ratio of the TA/Ag+ and the SG/Ag+. The results of antioxidation tests of Cu/Ag powders provided the evidences that the surfaces of copper powders were coated with a continuous layer of silver. The conductivity measurement showed that the resistivity of the Cu/Ag powders with 10 mol % silver content was 21.73×10-3Ω．cm, which is close to the resistivity of silver, i.e. 4.85×10-3Ω．cm.
　　Disk diffusion studies with E. coli (ATCC 15480) and S. aureus (ATCC 15285) revealed excellent antibacteria effects of the Cu/Ag powders. The antibacteria effect become more significant with the increase of the silver content of the Cu/Ag powders.

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