ZnO/Er2O3 core–shell nanorod arrays: Synthesis, properties and growth mechanism.

In this study, we demonstrated large-scale ZnO/Er 2 O 3 core–shell nanorod arrays, which were successfully synthesized by a facile and simple electrodeposition method. The effect of varying the amount of Er 2 O 3 in the range from 0.2 g to 1.0 g on morphology of ZnO nanorod arrays has been thoroughly investigated. The results indicate that the growth pattern of all the ZnO/Er 2 O 3 shell–core nanorod arrays were along c -axis and perpendicular to the substrate as before, even more vertical. Photoluminescence measurement was carried out and the PL peaks at 382 nm, 438 nm and 462 nm were observed, which are considered to be due to free excitons and donor-bound excitons, respectively. The ZnO/Er 2 O 3 core–shell nanorods exhibited improved optical property, which can be attributed to the enhanced donor density by the covered Er 2 O 3 . Finally, a possible growth mechanism of the ZnO nanostructures is discussed. The electrochemical deposition of ZnO/Er 2 O 3 core–shell nanorod arrays including two stages, namely nucleation and growth process. [ABSTRACT FROM AUTHOR]