Synthesis of monocrystalline zinc oxide microrods by wet chemical method for light confinement applications

The growth of Zinc Oxide (ZnO) microrods by wet chemical method, under prolonged treatment of zinc nitrate for 22 h in low temperature (80 °C) with hexamine is presented. The purpose was to obtain large microrods that can act as laser resonators with emission in the blue region. The electron microscopy and X-ray diffraction observations reveal that the ZnO microrods are single crystalline. We have done various optical characterizations in order to assess the suitability of the rods in photonic applications. Studies include optical absorption, fluorescence and photon backscattering. Room temperature optical measurements reveal that they have a large direct band gap of 3.7 eV and an emission at the visible and ultraviolet region and have excitation wavelength dependence. The backscattering studies clearly reveal the photon confinement effects, which is the first test of the materialʹs self lasing action.