Low temperature dielectric studies of zinc oxide (ZnO) nanoparticles prepared by precipitation method

Using zinc nitrate as a precursor and NaOH starch as a stabilizing agent, hexagonal zinc oxide (ZnO) nanoparticles has been synthesized by precipitation method. The transmission electron microscopy (TEM) images show particles of nearly uniform spherical size of around 40 nm. The infrared spectroscopy (FT-IR) measurement reveals the peak at 500 cm−1, corresponding to the Zn–O bond. Dielectric studies of ZnO nanoparticles show frequency dependence dielectric anomaly at low temperature (85–300 K). Results reveal that the capacitance and loss tangent decrease with the frequency while these parameters improve with the increasing of temperature. The increase of a.c. conductivity with the temperature indicates that the mobility of charge carriers is responsible for hopping and electronic polarization in ZnO nanoparticles.

Graphical abstractUsing zinc nitrate as precursors and NaOH starch as a stabilizing agent, hexagonal zinc oxide (ZnO) nanoparticles has been synthesized by precipitation method.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesized hexagonal ZnO nanoparticles by precipitation method using ZnNO3 and NaOH starch. ► Report frequency dependence dielectric anomaly at low temperature (85–300 K) in ZnO nanoparticles. ► Enhancement of the dielectric response of ZnO nanoparticles in the low-frequency range.