Redox of NiO thin film on YSZ (111) substrate

Abstract

The effect of redox process on the microstructure and composition of NiO thin film deposited on YSZ (111) substrate at room temperature by radio frequency sputteringmethod was investigated by transmission electron microscopy (TEM). The orientation relationship of NiO (002) or NiO (11̄1) plane paralleling to YSZ (11̄1) plane with NiO [110] paralleling to YSZ [110] was observed. After reduction, Ni (11̄1) plane paralleled to YSZ (11̄1) or YSZ (002) plane. Both reduction and oxidation processes started at the surface. A very thin nickel oxide layer remained even after reduction, which might result from oxygen transfer from YSZ to the interface. The formation of nickel oxide clusters with voids after reoxidation was due to the imbalanced transfer between the outward nickel and inward oxygen diffusions. Copyright © 2012 John Wiley &Sons, Ltd.