Fabrication of Metallic Nanowire Arrays with Excellent Ferromagnetic Performance

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06508
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Material processing/Microstructural control engineering
• Research Institution: Nagasaki University
• Principal Investigator: OHGAI Takeshi 長崎大学, 工学研究科, 准教授 (60253481)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 陽極酸化 / 電析 / ナノチャンネル / ナノワイヤー / コバルト / 結晶配向性 / 保磁力 / 角型比

Outline of Final Research Achievements

Ferromagnetic nanocomposite thick films, which contained (002) textured hcp-Co nanowire arrays, were synthesized by potentio-static electrochemical reduction of Co2+ ions in anodized aluminum oxide (AAO) nanochannel films. The aspect ratio of hcp-Co nanowires with diameter in ca. 25 nm reached up to ca. 1,800. Texture coefficient, TC002 increased with decreasing the overpotential for hcp-Co electrodeposition by shifting the cathode potential nobler than the transition potential, Etra (ca. -0.77 V vs. Ag/AgCl). In a similar way, TC002 increased sharply with decreasing the growth rate of hcp-Co nanowires smaller than the transition growth rate, Rtra (ca. 600 nm s-1). Perpendicular magnetization performance was observed in AAO nanocomposite films containing hcp-Co nanowire arrays. With increasing TC002, coercivity of the nanocomposite film increased and reached up to 1.66 kOe with the squareness of ca. 0.9 at room temperature.

Free Research Field

金属表面工学