Synthesis of ZnO nanorods by one step microwave-assisted hydrothermal route for electronic device applications

Abstract

In the present work, zinc oxide (ZnO) nanorods (NRs) were prepared by a simple Microwave-assisted hydrothermal synthesis route by using a 100 ml Teflon container. The structural, crystalline nature and purity of the synthesized material was studied by powder X-ray diffraction studies. The optical absorption wavelength observed at 368 nm has been shifted to 377 nm during hydrothermal synthesis of ZnO NRs. The shifting of wavelength reduces the energy band gap from bulk state of 3.52–3.32 eV during the Microwave-assisted hydrothermal process. There is no shift in peak observed in photoluminescence spectrum between ZnO NRs and ZnO nanoparticles (NPs) but increase in temperature increases the Deep Level Emission (DLE) intensity due to the loss of oxygen during the hydrothermal process. The FTIR analysis confirms the presence of various functional groups in the ZnO NRs and NPs. The elemental, shape and surface morphology of the ZnO NRs and NPs were determined by using EDAX and FE–SEM analysis. The surface properties of ZnO NPs and ZnO NRs were studied by BET analysis. Thermal stability of the material was increased from 180 to 277 °C after the hydrothermal synthesis. The zeta potential analysis reveals the stability of the synthesized ZnO nanostructures. The variation of dielectric constant, dielectric loss and ac conductivity with frequency for the various temperatures was measured and discussed the suitability of the material for the electronic device fabrication.