Li-Diffusion in Spinel Li[Ni_1/2Mn_3/2]O₄Powder and Film Studied with μ⁺SR

Abstract

A dynamic behavior in spinel Li[Ni 1/2 Mn 3/2 ]O 4 has been studied with µ + SR measurements in film and powder samples in the temperature range between 5 and 500 K. Both samples exhibited a broad ferromagnetic transition below 120 K, indicating the random distribution of Ni and Mn ions at the octahedral 16d site. Above 150 K, the ZF-µ + SR spectrum showed a dynamic behavior well explained by a dynamic Kubo-Toyabe function. Assuming a jump diffusion of Li + at the tetrahedral 8a site to the vacant octahedral 16c site, a diffusion coefficient of Li + is estimated as ∼ 5×10 −11 cm 2 /s at 300 K and ∼ 8 × 10 −11 cm 2 /s at 350 K and ∼ 14 × 10 −11 cm 2 /s at 400 K, with thermal activation energy E a ∼ 0.1 eV.

Photophysical Ion Dynamics in Hybrid Perovskite MAPbX3 (X=Br, Cl) Single Crystals

“…Furthermore, their study has been conducted on MAPbI 3 powder sample, giving an average of the diffusion length among multiple directions and influenced by grain boundaries. [26] Finally, their measurement does not consider the effect of illumination, which can drastically influence the dynamics of ions.…”