The sol-gel process was applied for the preparation of neodymium (Nd3+)
doped silica gel derived glasses. Two different procedures have been studied
using two different precursor materials, Tetramethoxy-silane (TMOS) and
Tetraethoxy-silane (TEOS), giving silica gel and silica doped with Nd3+ of type
I and type II, respectively. Both type materials were subjected to the same heattreatment
temperature. The normal transmission was measured using Fourier
Transform Infrared Spectrometer FTIR, Raman analysis and X-ray diffraction
(XRD), were carried out to determine the crystal structure of the prepared
samples. The prepared samples change from amorphous to ∝-crystoballite
phase at higher temperature regardless the two type materials. The crystallite
size was found to be as small as 10.4 nm at 1400oC for pure sample type II. The
thermally treated sample microstructures were investigated using scanning and
transmission electron microscope. Also DTA and TGA Characteristic
techniques were used. The photoluminescence PL measurements for pure
sample (type I) heat-treated at 1400oC shows bands of maximum in the blue
green spectral region at 535 and 546 nm accompanied with band of weak
intensity at 590 nm. Doped sample (type I) heat-treated at 1400oC shows new
bigger, sharper and intense bands at 875, 889 and 900 nm that were interpreted
on the light of 4F3/2 to 4I9/2 transitions of Nd3+ ion. PL spectra are found to be
sensitive to defects such as impurities and E' centers.