Ultrasound Assisted Synthesis and Properties of ZnO:B Nanorods and Micro Flowers

Nanopowders of ZnO pure and doped with boron have been synthesized through sonochemical method using acetate of the material as starting reagent. The incorporation of boron has been confirmed by inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis. Continuous (CS) and pulsed (PS) mode syntheses have shown interesting structural and optical properties such as photoluminescence (PL) and ultra-violet (UV) absorption. X-ray diffraction (XRD) studies showed broadening and shifting of peaks with boron incorporation in ZnO leading to size reduction in doped samples. The structure of the nanoparticles was found to be rod like and these rod like structure coalesce in boron doped ZnO. This has been explained on the basis of nucleation of octahedral units in the beginning leading it to tetrahedral structure. Electron microscopy has been used to explain these results. Definite peak shifts towards low wavelength side in absorption band and photoluminescence spectra have been observed for smaller particle size in pulsed mode powder. The blue shift due to particle size has been explained in the light of quantum confinement effect.