Optical band-gap and dielectric behavior in Ho - doped ZnO nanoparticles

The optical band-gap and dielectric properties of Zn1-xHoxO delta nanoparticulate powders with x=0.0, 0.005, 0.0075, 0.01, and 0.015 prepared by combustion reaction (CR) method were investigated at room temperature. Both optical band-gap, Eg, and dielectric constant, epsilon', values increased with increasing Ho doping concentration; being similar to 3.234 and similar to 3.268 eV, and similar to 37 and similar to 50 for x=0 and 0.015, respectively at room temperature. The dielectric behavior was described by the Cole Cole model (Cole and Cole, 1941) [22] and the results were discussed in terms of defects such as oxygen vacancies VO or/and interstitial oxygen O present in Ho - doped ZnO nanoparticles, introduced during the sample preparation. (C) 2016 Elsevier B.V. All rights reserved.