Optical properties of ZnO nanoparticles synthesized by co-precipitation method using LiOH

Abstract

ZnO NPs have been successfully synthesized at room temperature by the co-precipitation method using LiOH. All the detected X-ray diffraction peaks along (100), (002), (101), (102), (110) and (103) planes confirm the formation of hexagonal wurtzite structure of ZnO. The crystallite size lies between 18-39 nm. The sharpness of the diffraction peaks indicates good crystallinity of ZnO NPs. The UV-Vis absorption spectrum shows strong absorption peak at 382nm and the optical band gap of is determined to be 3.14 eV. The photoluminescence emission spectrum recorded with an excitation wavelength of 325 nm shows peaks centered at 408 & 426nm, 453nm, 488 and 530nm with a shoulder at 582nm. FESEM shows some cauliflower-like structures which are combination of quasi-spherical grain with average grain size 57nm.