A comprehensive study on the influence of Mg doping on structural, AC conductivity, and dielectric behavior of ZnONPs

Abstract

In this research magnesium (Mg) doped zinc oxide nanoparticles (Zn1-x MgxO, where x = 0 for pure ZnO) were synthesized using a simple chemical route. Their structure and morphology was characterized using different methods, such as X-ray diffraction, scanning electron microscopy, Fourier Transform spectroscopy, photoluminescence. Nanoparticles (NPs) were synthesized and analyzed for their structure, shape, chemical content, and optical and dielectric activity with Zn1-x MgxO (where x = 5,15,50 wt%). The crystalline, hexagonal ZnO was verified by X-ray diffraction, with an average grain size of 45 nm for ZnO and 28 nm for Mg doping and a more interplane spacing that ranges from 2.9 nm to 18 nm. In the nanoscale domain, with a hexagonal crystalline shape between 30 and 80 nm, Zn1-x MgxO were analyzed in scanning electron microscopy (SEM) pictures. Transmittance rises with doping, as shown by optical characterization, and UV–vis spectroscopy reveals low absorbance in the visible area. Absorption values drop dramatically for all samples in the UV region, and when magnesium content rises, the absorption peak moves to shorter wavelengths. As the Mg content increased from 5 % to 50 %, the optical absorption spectra of ZnO switched to red. The UV emission peak in PL spectra was seen between 389 and 700 nm. It revealed that up to 50 % Mg doping, the strength of the emission bands at 405 and 525 nm decreases. According to fluorescence emission, zinc oxide has interaction with porphyrin, which results in a new peak at 389 nm. This 389 nm peak is thus specific to ZnO and Zn1-x MgxO nanoparticles as a result of the electron transport between the two materials. The Zn1-x MgxO samples show low dielectric losses and high dielectric constants in the middle and high-frequency ranges. The Mg doping at 5 % concentration is particularly intriguing since it shows enormous dielectric constant across a broad frequency range. At low frequencies, all the samples suffer from a significant loss factor. In the high-frequency range, it stabilizes.