Deep level emission of ZnO nanoparticles deposited inside UV opal

Abstract

The temperature-dependent photoluminescence (PL) spectra of zinc oxide (ZnO) nanocrystals deposited inside the ultraviolet (UV) opal were studied. ZnO was grown in the voids between FCC packed SiO 2 spheres using spray pyrolysis under ultrasonic vibration in the solution containing a zinc nitrate precursor. The ZnO nanoparticles inside opal matrix with UV photonic band-gap exhibit suppression of the excitonic emission and enhancement of the deep level emission. Suppression of the excitonic lines is due to the inhibition of spontaneous emission, while enhancement and broadening of the DL emission in the green spectral region is due to Purcell effect. The infiltration of ZnO inside the photonic crystal may be a useful technique to increase its emission efficiency in the selected spectral region.

Broadening of band-gap in photonic crystals with optically saturated media

“…The growth procedure of the polycrystalline nanoparticles of ZnO in 3D bulk opal and the effect of PBG on the green [21] and UV [22] PL spectra were shown first in our publications. For the soaking of the samples we applied deionized water solution containing zinc nitrate hexahydrate (Zn(NO 3 ) 2 •6H 2 O) precursor, used earlier by our research group [18].…”

Solubility enhancement and epitaxial core–shell structure of Si-doped ZnO via a specific pulsed laser ablation route

“…It is an open question whether the occasional Si dopant in between 4-and 6-coordinations, as manifested by Raman shift, contributed also to the blue and/or green luminescence. In any case, the PL intensity of W-ZnO in ZnO-SiO 2 environment is several orders of magnitude higher than pure ZnO, indicating that the rate of spontaneous emission depends partly on the environment of the light source, i.e., Purcell effect, analogous to the case of ZnO NPs embedded in SiO 2 opal [53].…”

Cellulose photonic crystal film sensor for alcohols

“…The values 0.74 and 0.26 are the filling factors for the host material (colloidal) and air, and f is the filling factor for CPCFS [34,35]. The reflection wavelength can be shifted by altering the lattice parameters or the mean effective refractive index.…”