[21p-N302-1~10] 6.3 Oxide electronics

△ [21p-N302-7] Synthesis and fast H⁻ conduction of new lanthanum oxyhydride LaH_3−2xO_x

〇(D)Keiga Fukui¹, Soshi Iimura¹, Tomofumi Tada¹, Satoru Fujitsu¹, Masato Sasase¹, Hiromu Tamatsukuri², Takashi Honda², Kazutaka Ikeda², Toshiya Otomo², Hideo Hosono¹ (1.Tokyo Tech., 2.KEK)

Keywords:ionic conduction, hydride ion, oxyhydride

We investigated hydride ion conduction in newly found lanthanum oxyhydride, LaH_3−2xO_x (0 < x < 1). X-ray and neutron diffraction revealed that the LaH_3−2xO_x crystalizes a fcc structure, and the hydrogen partially occupies the tetrahedral and octahedral sites. We measured the ionic and electronic conductivities by AC impedance and DC polarization techniques, respectively. An optimum ionic conductivity at 340°C reached 2.6×10⁻² S cm⁻¹ at x = 0.25, where the transport number of H⁻ exceeded 99%.