Influence of metal doping on topographic, microstructural, optical and thermal properties of zinc oxide nanoparticles

In this research, pure zinc oxide nanoparticles PZONP) and cobalt (Co) doped ZONP (CDZONP) at different doping levels were fabricated via a lucrative chemical bath deposition (CBD) method to investigate the effect of Co doping on the morphologal, structural, thermal, and optical properties. The scanning electron micrographs displayed a slightly olive-like structure of PZONP which altered to flower-like structure after Co doping. Spherical-shaped nanoparticles are present in the prepared 5% CDZONP with a surface roughness of 17.32 nm as observed by atomic force microscopic. X-ray diffraction analysis explored that PZONP, 5% CDZONP and 10% CDZONP represent hexagonal wurtzite and simonkolleite structures respectively. The computed crystallite size of PZONP significantly altered from 149.47 to 125.05 nm with increasing Co content. Thermogravimetric analysis indicated the enhancement of thermal stability of CDZONP as compared to PZONP. Optical analysis revealed that with the increase of Co doping, a little shift of the absorption edges happened. Band gap energy values were decreased monotonically with Co doping from 2.96 eV for PZONP to 2.53 eV for 10% CDZONP. The stable and suitable optical band gap of the 5 wt % CDZONP could be of potential material in the field of optoelectronic devices.