A structural property study on the role of Sm ions in nano-textured Zn(1-x)Sm (x) O thin films for green emission

Abstract

Sm doped ZnO nanocrystalline textures were deposited through pyrolytic reactions on preheated glass substrates to tune the green emissions from the wurtzite matrix. The textures were found to be well-defined, possessing grain like morphology; with their dimensional parameters depending on the level of Sm substitution. The films were then characterized using several analytic techniques to establish the origin of their green emissions. The structural data obtained using the 2 theta plots revealed the polycrystalline nature of the species and their preferred orientation along (002) plane. The morphology studies revealed a gradual decrease in grain size, while increasing the Sm composition. Their evolution has been correlated with the heterogeneous nucleation taking place on the surface of the substrate. The role of defects and crystallinity of the Zn1-xSmxO has been explained using Raman spectroscopy. Taucs plot revealed a red shift in the optical energy band gap of the species, while the luminescence spectra illustrated the enhancement of green emissions.