Study on characteristics of silicon nanocrystals within sol–gel host

Abstract

In this article, luminescent Si nanocrystalline (NC) powder was uniformly dispersed in dimethyl sulphoxide and then incorporated into the SiO 2 gel matrix. Inorganic precursor tetraethylorthosilane was diluted in ethanol to form a homogenous solution. Dimethylformamide was used as a drying control chemical additive. Absorption and emission spectra of Si NPs in the silica gel with respect to time were recorded systematically at room temperature. The study reveals that the absorption and emission spectra of Si NPs, when doped in sol-gel silica matrix are modified. Influence in the band strengths and their peak positions upon ageing time are discussed. TEM shows existence of Si NPs of size ranges from 5 to 10 nm. Si NCs-doped sol-gel cylindrical rod was prepared and cut at different lengths from 10 to 15 mm to measure the optical gain. Photoluminescence stability of Si NCs in sol-gel is found for several weeks under the UV lamp.

Optical Characterization of Chemically Etched Nanoporous Silicon Embedded in Sol‐Gel Matrix

“…The absorption peak positions of NPs in THF, sol and sol-gel solid are listed in Table 1. Our earlier work on the silicon nanocrystallines powder in sol-gel obtained as similar to present results [28]. On the other hand, from the theoretical point of view reported in [30] that significant influences of the matrix material on the electronic The origin of 325 nm absorption band may consider to the work reported [31] that the optical absorption of Si at 320 nm (4 ev) relatively size nanocrystals (d = 3.7-10 nm) is associated with direct transition Γ 25 -Γ 2 .…”

“…In spite of many attempt to describe the PL properties of Si nanoparticles produced by various techniques, a proper assignment of individual emission features of the Si nanoparticle-doped sol-gel in terms of optical, thermal, mechanical properties and is still limited. Earlier our work reported on the basic optical properties of Si nanocrystals powder in sol-gel matrix and discussed their PL stability [27,28]. The aim of this present work is to understand the PL properties of the nanoporous silicon fabricated by chemical etching process in sol-gel matrix.…”

Comparative Study on Electronic, Emission, Spontaneous Property of Porous Silicon in Different Solvents

“…Because, demonstration of Psi/nc-Si in sol gel is easily manageable, that enables the fabrication of samples with high densities of silicon nanoparticles for optoelectronics purposes. Due to being greatly important to optical stability of Psi/nc-Si within sol gel matrix in view of light stimulation, recently systematic studies were done by our group especially on PL and structural properties of the NCs powder [20,21], nanoporous silicon [22,23] in sol gel host. Although porous silicon could stabilize in the sol gel active medium, weak emission and spontaneous signals were obtained due to low concentration of Psi colloidal solutions.…”

Fabrication and amplified spontaneous emission behavior of FAPbBr3 perovskite quantum dots in solid polymer rods

“…PQ-Dots were successfully encapsulated or incorporated in silica [63], highly luminescent lead halide Q-Dots in hierarchical CaF 2 matrix [64], and luminescent lead bromide/NaNO 3 nanocomposite matrix [65]. Similarly, the optical properties [76] and structure of silicon NCs [77] in sol-gel matrix was studied, and significant, stable PL was observed. The morphology [78] and optical property of different types of colloidal porous silicon [79] doped in sol-gel matrices or oxide environments were studied, but this was not suitable for PQ-Dots due to the involvement of water.…”