Electrochemical synthesis of Ag/Co multilayer structure nanowires

• Main Authors: Chih-Yung Wang, 王智永
• Other Authors: Tsung-Shune Chin
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/77924945557097957643

碩士 === 國立清華大學 === 材料科學工程學系 === 91 === Synthesis and study of nano material attract more attention in recent years. One-dimension nano structure including nanowire、nanorod、nanotube have many amazing property like high density；high surface aspect ratio、field-emission and etc. On the other hand, multi-layer thin films structure such as superlattice also has been studied with its special application in electric industry. The main goal of this paper is to combine the two different structures as above with single bath electrodeposition method to fabricate Ag/Co multi-layer nanowire in the AAO template, which its pore diameter could be controlled in nanometer range. The electrolyte system used in the experiment containing CH3COONH4、AgNO3、CoSO4‧7H2O is developed by our own. Cyclic-Voltammetry and Ag/Co electrodeposition rate competing analysis show the overall reduction action is mainly controlled by the [Ag+]. When [Ag+] is increased, the Ag reduction rate will be highly promoted to break the competition effect designed before. We also find that Electrodepositing Ag and Co within the AAO template contains some problems on the interface of Co/Ag+ such as self oxidation-reduction reaction and electrolysis during lower potential interval. By the way, we also can change the electrochemical condition to synthesis nano alloy wire with different composition. In this condition: CH3COONH4：0.4M，AgNO3:0.5mM，CoSO4‧7H2O：0.15M , Ag 0.65V，Co 0.9V , Ag 200sec，Co 100sec，off time 20sec, we can successfully get the multi-layers nanowire with [Co99.43Ag0.57]/ [Ag53Co47] and [Co65Ag35]/[Ag80Co20] structures. Pure Co nanowire、Ag/Co nano alloy wire and Ag/Co multi-layers nanowire. Ag/Co nano alloy wire have such different result in magnetic analysis has more obvious anisotropy and saturation magnetization(Ms) than pure Co nanowire；Ag/Co multi-layers nanowire has obvious anisotropy but lower Ms than alloy nanowire.