Comparison of theoretical and experimental microhardness of tetrahedral binary Zn<inf>1-x</inf>Er<inf>x</inf>O semiconductor polycrystalline nanoparticles

Abstract

Zn1−xErxO polycrystalline nanoparticles with various compositions (x=0.01,0.02,0.03,0.04,0.05, and 0.10)were prepared using sol–gel techniques, for which zinc acetate dihydrate and erbium 2–4 pentanedionate are used as precursors. Nanoparticles were pressed under a pressure of 4 tons for 5 min into disk-shaped compacts with 2 mm thicknesses and 10 mm diameters. The pressed samples were annealed at 400 °C for 30 min. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Vickers microhardness analyses of the produced Er-doped ZnO bulk nanomaterials were performed. Specifically, in this study we focused on the analysis of their mechanical properties. Undoped and Er-doped bulk samples were investigated according to Meyer's law; the proportional sample resistance (PSR), elastic/plastic deformation (EPD), and indentation-induced cracking (IIC) models; and the Hays–Kendal (HK) approach. As a result, the IIC model was more suitable to determine the micromechanical properties and the reverse indentation size effect (RISE) behavior of Er-doped ZnO semiconductors.