Measurements of local ionic conductivities around ferroelectric/solid electrolyte interface

• Project/Area Number: 25288115
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Device related chemistry
• Research Institution: Nagoya University
• Principal Investigator: IRIYAMA Yasutoshi 名古屋大学, 工学(系)研究科(研究院), 教授 (30335195)
• Co-Investigator(Kenkyū-buntansha): MOTOYAMA Munekazu 名古屋大学, 工学研究科, 講師 (30705752)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥15,730,000 (Direct Cost: ¥12,100,000、Indirect Cost: ¥3,630,000); Fiscal Year 2015: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2014: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2013: ¥11,050,000 (Direct Cost: ¥8,500,000、Indirect Cost: ¥2,550,000)
• Keywords: 二次電池 / 界面 / 原子間力顕微鏡 / 全固体電池 / 固体電解質 / 複合体 / イオン伝導率 / 空間電荷層 / 電池

Outline of Final Research Achievements

Complex dielectric constant of ionic conductive materials have concerned with the ionic conductivities. We developed a measurement system to estimate local dielectric constant of glass electrolyte by using amplitude modulation type atomic force microscopy (AM-AFM). Thin films of lithium phosphorus oxynitride glass electrolyte (LiPON) were prepared on highly oriented pyro graphite substrate and measure the dielectric constant. The measured value, ca. 20, was in good agreement with the reported valuw (16-20), indicating that our measurement system works well. Then, we evaluated the voltage dependency of dielectric constant around the BaTiO3-LiPON interface. The AM-AFM observations suggested a formation of a region around the interface, where higher dielectric constant was observed against the value measured in the bulk.