An article available as a pre-proof in the journal Materials Today: Proceedings focuses on sol-gel nanocomposites specifically utilized for optical applications.
Study: Optical applications of sol-gel nano-composites. Image Credit: S.Gvozd/Shutterstock.com
Introduction to Sol-gel Nanocomposites
The invention of sol-gel nanocomposites has been primarily motivated by their potential applicability in a wide variety of uses, and commercialized sol-gel nanocomposites are now an essential feature of fabrication techniques. Around the end of the 1980s, the utilization of sol-gel technology for the fabrication of polymer nanocomposites began to surface in the literature.
One of the most intriguing aspects of the sol-gel method for nanocomposites is the ability to obtain them as thin films to encapsulate any sort of platform, and many possibilities include high-tech coverings and resins.
Synthesis of Sol-gel Nanocomposites
Nanocomposite materials hold great potential since they could provide the required stability and ease of fabrication for these critical applications. For at least one phase, sol-gel nanocomposites are created via the sol-gel technique. They were obtained in two ways: "in situ" and "ex-situ." The first approach has the benefit of generating both the matrix and the dispersed phase from the very same batch of antecedents, but the second approach, which is dependent on scattering already manufactured dispersed phases in the matrix sol, gives superior micro-hardness tolerances.
Applications of Sol-gel Nanocomposites
Owing to their manageable physical and chemical characteristics such as size, surface characteristics, stoichiometry, and crystalline lattice, as well as their configurable excellent biocompatibility, sol-gel nanocomposites are widely used as biomaterials.
Sol-gel nanocomposites are commonly employed in sensing devices. Sol-gel coating is reasonably easy to scale up to an industrial level and is particularly well suited to film deposition. The approach is also not costly in the case of thin sheets, where the expense of precursors is low. For these reasons, sol-gel may present exciting difficulties in the realm of chemical sensors, and it is now being studied extensively. In addition, one of the most researched technologies for sol-gel nanocomposites covering is a hard coating, which is also one of the most prospective for commercial processes.
The need for novel optically efficient and translucent substances rises in tandem with the plethora of requests for optical materials. Aside from optical demands like switches and amplifiers, the substance should be integrated with existing infrastructures like waveguides and fiber optics. For all these requirements, sol-gel nanocomposites could play an essential role.
Integration of Quantum Dots in Nanocomposite Films
Semiconductor quantum dots (QDs) have size-dependent properties due to charge carrier restriction. Controlling the emission spectra, as well as fluorescence quantum performance and stabilities, offers up new avenues for photonics and optoelectronic technologies. The QDs dispersions are blended into the sol-gel mixtures, yielding a final sol that may be utilized to make thin films. Before these nanocomposite substances can be employed to manufacture devices, they must be processed utilizing a standardized method.
Titanium Dioxide Applications
Titanium dioxides' most prevalent crystalline structures are anatase and rutile, rendering it one of the most researched materials for gas sensor applications. A variety of gas sensors were created using TiO2 as the core of the sensing material. TiO2-Au films were created by synthesizing Au NPs using emulsion methods and then dispersing them in titania-based sol-gel mixtures following filtration and surface modification.
Zinc Oxide Applications
Zinc oxides are one of the most researched materials for gas sensing, detecting a broad array of volatile matter, including oxygen, CO, H2, ammonia, and a variety of volatile organic chemicals (VOCs). It may also be actuated by any heat or UV radiation, allowing the development of low-temperature detectors. By dissolving zinc acetic acid dihydrates in alcohol in the vicinity of monoethanolamine, ZnO sol-gel films have been effectively created.
Organic-Inorganic Hybrid Sol-gels
A combination organic-inorganic sol-gel composition might be used to distribute Au colloid. Au emulsion is employed to form sub-monolayers on top of the PSQ sol-gel matrices, or they are embedded in the PSQ matrix.
PSQ sol-gel materials have also been deposited on complicated metallic structures with nanoprisms patterns produced by combining microsphere imaging and thermal deterioration. A simple and basic process based on alternate depositions of regenerated silken was used to create the multilayer structure.
In short, the multipurpose nanocomposites based on a combination of QDs in inorganic or fusion organic-inorganic matrix have been studied, revealing a stabilization of optical property, strong chemical durability, and ease of fabrication.
Surekha P. et. al. (2022) Optical applications of sol-gel nano-composites. Materials Today: Proceedings. Available at: https://www.sciencedirect.com/science/article/pii/S2214785322010537