Ionic distribution analysis at electrode/electrolyte interfaces in energy storage devices

2015 Fiscal Year Final Research Report

• Project/Area Number: 25410237
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Inorganic industrial materials
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Hirayama Masaaki 東京工業大学, 大学院総合理工学研究科, 准教授 (30531165)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 電気化学材料 / 表面散乱 / 界面反応解析

Outline of Final Research Achievements

The electrochemical interfaces between intercalation electrodes and organic electrolytes were investigated by in-situ neutron reflectometry using epitaxial-film model electrodes. The depth profile of the scattering length density as determined by neutron reflectometry clarifies the ionic distribution at the interface owing to high sensitivity of lithium ions. A phase transition occurs in the surface 20 nm region of the film electrodes from the top surface, and the reconstructed phase determines electrochemical properties during the subsequent cycles. Using neutron reflectometry, X-ray diffractometry, and X-ray photoelectron spectroscopy in combination, it is found that the surface structures and electrochemical properties can be controlled by surface modification. Direct observation and control of the interfacial structure is an effective way of developing intercalation materials with high capacity, high power, and high stability.

Free Research Field

固体化学，電気化学