Effect of Gallium doping on structural, optical and electrical properties of ZnO nanoparticles prepared in gelatin media

In this work, Zn1-xGax O (x = 0.00, 0.01, 0.03, 0.05) nanoparticles were prepared by using sol-gel method in gelatin media and all the samples were crystallized in single phase wurtzite structure. Average particle size was estimated 20 nm using TEM technique. XRD Analysis showed that average crystalline size of 0.01 Ga-doped sample decreased comparing to the undoped ZnO while average crystallite size the samples with higher Ga content increased with further dopant agent content. The UV-vis absorption spectra showed that absorption edge of the doped samples shifted to lower wavelengths and optical band gap shifted to higher energies comparing to the undoped one. The current-voltage (I-V) curves of samples showed that resistance of the samples increased with the increase in doping agent content. This increase in resistance can be attributed to decreasing oxygen deficiency and carrier density in the structure due to presence of Ga dopant.