Structure and electrical properties of Mg‐doped ZnO nanoparticles

Abstract

Mg x Zn 1-x O (x=0.01-0.3) nanoparticles were synthesized by the sol-gel technique using solutions of Mg and Zn based organometalic compounds. The electrical properties of Mg doped zinc oxide (ZnO) were studied within wide temperature range from 300 to 500 K under the N 2 gas flow (flow rate: 20 sccm) and in the frequency range from 40 Hz to 1 MHz for ac electrical measurements. The dc conductivities and the activation energies were found to be in the range of 10 -9 -10 -6 S/cm at the room temperature and 0.26-0.86 eV respectively depending on doping rate of these samples. The ac conductivity was well represented by the power law Aω s . The conduction mechanism for all doped ZnO could be related to correlated barrier hopping (CBH) model. The complex impedance plots (Nyquist plot) showed the data points lying on a single semicircle, implying the response originated from a single capacitive element corresponding to the nanoparticle grains. The crystal structures of the Mg x Zn 1-x O nanoparticles were characterized using X-ray diffraction. The calculated average particle sizes values of Zn 1-x Mg x O samples are found between 29.72 and 22.43 nm using the Sherrer equation.

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