Sol-Gel Glass Coating Synthesis for Different Applications: Active Gradient-Index Materials, Microlens Arrays and Biocompatible Channels

Abstract

The intent of this chapter is to review the use of sol-gel processing of silica and silica-titania optical coatings in recent research by the authors in three different areas: the synthesis of active gradient-index (GRIN) materials by multilayer deposition of erbium-and ytterbiumdoped silica-titania films, the improvement of the optical and morphological qualities of microlens arrays fabricated by laser ablation and the functionalization of polydimethylsiloxane (PDMS) channel preclinical devices. Through the use of sol-gel, layers with specific properties can be produced. In this regard, undoped and erbium-and ytterbium-doped SiO 2-TiO 2 films have been produced and characterized using atomic force microscopy (surface topography evaluation) and spectral ellipsometry (determination of optical constants, thickness and porosity of the films). In a second application, a silica sol has been synthesized to coat microlens arrays fabricated by laser ablation. The deposited layer reduces the surface roughness of the microlens array, which yields the improvement of the contrast and the homogeneity of the foci. Finally, PDMS channels fabricated with laser technologies and soft-lithography methods are coated with a sol-gel-derived silica film to avoid the degradation of the material with organic solvents, and their biocompatibility is studied.

P-Type Metal Oxide Semiconductor Thin Films: Synthesis and Chemical Sensor Applications

“…The experimental procedure for a standard dip-coating technique is shown in Figure 11 [ 75 ]. The dip-coating method has been used to prepare many p-type MOX thin films, such as CuO, NiO, Co 3 O 4 , and Cr 2 O 4 .…”

“… Schematic of the processes controlling thin-film formation in fast- and slow-rate deposition. Reprinted with permission from [ 75 ]. …”

Modern Smart Street Light Monitoring Systems

“…Regular cleaning and maintenance protocols should be implemented to remove water stains and prevent fogging. In order to overcome these demerits, it's always better to create superhydrophobic surfaces on silica glass which is used for streetlight applications [29][30][31]. The sol-gel method is a versatile and precise technique for preparing superhydrophobic coatings with numerous advantages.…”

Large Area Patterning of Nanoparticles and Nanostructures: Current Status and Future Prospects

“…Many parallel techniques have utilized the wetting and self-assembly properties of NPs, sometimes in conjunction with templated substrates, to form large-area NP arrays on areas as large as tens of square centimeters . Their advantage is that the patterns can be obtained quickly with simple laboratory equipment and on many different substrates (Figure e) . However, the precision in NP assembly and the reproducibility of the pattern are more challenging to control with parallel methods.…”

“…13 Their advantage is that the patterns can be obtained quickly with simple laboratory equipment and on many different substrates (Figure 1e). 14 However, the precision in NP assembly and the reproducibility of the pattern are more challenging to control with parallel methods.…”