Emission studies on ZnO-inverse photonic crystals derived from self-assembly

Abstract

Photonic crystals fabricated from the colloidal spheres of polymethyl methacrylate (PMMA) using the inward-growing self-assembly technique were subsequently in-filled with zinc oxide (ZnO) prepared by the sol-gel process. The polymer template was removed by heat treatment and chemical method to get ZnO-inverse photonic crystal. The structural quality of the inverse photonic crystal obtained by the chemical method was found to be superior to that obtained by heat treatment. The ZnO-inverse photonic crystal obtained by the chemical method was further treated at an elevated temperature to ensure the crystalline nature of ZnO. Laser-induced emission studies on ZnO-inverse photonic crystals were carried out at an excitation wavelength of 325 nm. The emission spectra showing UV and visible bands at collection angle of 45 degrees from the direction of excitation helped to establish the role of crystalline ZnO.