[18a-223-1~9] 6.3 Oxide electronics

[18a-223-8] Electrochemical reaction of NdNiO₃ thin films with NaCl solution

〇Ryosuke Ishigami¹, Akira Chikamatsu¹, Tsukasa Katayama¹, Miho Kitamura², Koji Horiba², Hiroshi Kumigashira^2,3, Tetsuya Hasegawa¹ (1.Univ. of Tokyo, 2.KEK, 3.Tohoku Univ.)

Keywords:NdNiO3, thin film, electrochemical reaction

Electrochemical reaction of NdNiO₃ thin films using NaCl aqueous solution was conducted. X-ray diffraction and Secondary ion mass spectrometry indicate that the insertion / deinsertion of hydrogen occured in the thin film by electrochemical reaction and the c-axis length expanded / contracted. X-ray absorption spectroscopy also shows that the valence states of Ni changed from Ni³⁺ to Ni²⁺ with hydrogen insertion. This indicates that hydogen was doped as H⁺ and valence states of Ni was reduced. In the lecture, we will also discuss the changes in physical properties.