Fabrication and Optical Property of Silicon Oxide Layer Coated Semiconductor Gallium Nitride Nanowires

Abstract

Quasi one-dimensional GaN-SiO(2) nanostructures, with a silicon oxide layer coated on semiconductor GaN nanowires, were successfully synthesized through as-synthesized SiO(2) nanoparticles-assisted reaction. The experimental results indicate that the nanostructure consists of single-crystalline wurtzite GaN nanowire core, an amorphous SiO(2) outer shell separated in the radial direction. These quasi one-dimensional nanowires have the diameters of a few tens of nanometers and lengths up to several hundreds of micrometers. The photoluminescence spectrum of the GaN-SiO(2) nanostructures consists of one broad blue-light emission peak at 480 nm and another weak UV emission peak at 345 nm. The novel method, which may results in high yield and high reproducibility, is demonstrated to be a unique technique for producing nanostructures with controlled morphology.

Photoluminescence of cerium–europium co‐doped SiO2 phosphor prepared by a sol–gel process

“…The well-known characteristic absorption bands, similar to those published elsewhere, 4,7 were observed from the FTIR data (not shown) near 453, 812 and 1083 cm 1 . In addition, the XRD data (not shown), consistent with the results of Zhang et al, 8 indicated that the SiO 2 powders were amorphous. The particle diameter estimated from SEM micrographs was between 1 and 3 µm.…”

Fabrication of CdS@TiO2 coaxial composite nanocables arrays by liquid-phase deposition

“…In the case, if semiconductors comprise the core and shell, the core-shell motif has permitted enhanced photoluminescence, improved stability against photochemical oxidation, enhanced processibility, and engineered band structures [1][2][3]. They are expected to have great potential applications for photoelectronic nanodevices, and electronic transportation [4,5].…”

Polarized measurements in Raman microscopy

“…The depolarization ratios were checked with a reference sample of liquid CCl 4 . The pinhole of the confocal microscope was closed at about 140 micron, which corresponded to a focal volume of about 1 micron cube, limiting significantly As reported by various authors for thin films 15,16 and for bundles of nanowires, 12,17 GaN that crystallizes in the hexagonal Wurtzite-type structure belongs to the space group (C 4 6v ) and has two formula units per primitive cell. According to the factor group analysis, the Raman active modes are 1A 1 (x 2 + y 2 , z 2 ) + 1E 1 (xz, yz) + 2E 2 (x 2 À y 2 , xy) while 2B 2 modes are silent.…”

“…The parameters A, B, C, D, E, can be determined assuming that the depolarization ratio r tends towards zero in resonant conditions and that one element of the polarizability tensor is dominant. Finally we can measure 6 spectra that are functions of the five hF i,j,k i order parameters as shown in (16,17).…”