What Is Driving the Growth of Inorganic Glass in Smart Materials and Opto-Electronic Devices?

Abstract

Inorganic glass is a transparent functional material and one of the few materials that keeps leading innovation. In the last decades, inorganic glass was integrated into opto-electronic devices such as optical fibers, semiconductors, solar cells, transparent photovoltaic devices, or photonic crystals and in smart materials applications such as environmental, pharmaceutical, and medical sensors, reinforcing its influence as an essential material and providing potential growth opportunities for the market. Moreover, inorganic glass is the only material that is 100% recyclable and can incorporate other industrial offscourings and/or residues to be used as raw materials. Over time, inorganic glass experienced an extensive range of fabrication techniques, from traditional melting-quenching (with an immense diversity of protocols) to chemical vapor deposition (CVD), physical vapor deposition (PVD), and wet chemistry routes as sol-gel and solvothermal processes. Additive manufacturing (AM) was recently added to the list. Bulks (3D), thin/thick films (2D), flexible glass (2D), powders (2D), fibers (1D), and nanoparticles (NPs) (0D) are examples of possible inorganic glass architectures able to integrate smart materials and opto-electronic devices, leading to added-value products in a wide range of markets. In this review, selected examples of inorganic glasses in areas such as: (i) magnetic glass materials, (ii) solar cells and transparent photovoltaic devices, (iii) photonic crystal, and (iv) smart materials are presented and discussed.

Keywords: inorganic glass; opto-electronic devices; smart materials.

Figure 1

Corning^® keeps leading innovation in high-tech glass materials: (a) Corning^® Gorilla^® Glass fabrication technic; (b–d) Corning^® Willow^® Glass, (b)—down-draw fabrication process, (c)—overflow fabrication process, and (d)—Flexible Corning^® Willow^® Glass product. ((b)—reprinted from [14] © (2010) with permission from Wiley; (c)—reprinted (adapted) with permission from [15] © (2016) American Chemical Society; (d)—reprinted from [16] © 2021 with permission from Wiley).

Figure 2

Examples of different glass fabrication methodologies. Melting-quenching: (a) glassblowing; (b) Lalique glass; (c) float chamber, credits by Saint-Gobain^® Glass Portugal; (d) Louvre Museum entrance, Saint-Gobain^®; (e) overflow fabrication process (reprinted (adapted) with permission from [15] © (2016) American Chemical Society); (f) Apple^® Willow^® glass watch; coatings and substrates; (g) SiO₂/TiO₂ Sol-gel coating on a standard glass substrate; (h) coated glass, Saint-Gobain, Paris, Valode & Pistre Architects, credits by Saint-Gobain^® Glass Portugal; (i,j) TFT backplane fabricated on flexible glass and flexible glass AMLCD prototype (reprinted from [75] © 2021 with permission from IEEE; Additive Manufacturing—Hollow Glass); (k) glass 3-D printing process by Steven Keating, MIT CC BY-NC-ND 3.0 available at [74], (l) by Andy Ryan, MIT CC BY-NC-ND 3.0 available at [74].

Figure 3

Soft magnetic materials (a) world market share (2016). A&T—automotive and transportation; Ind—industrial; E & I—electronics and instrumentation; EG—energy generation. (b) Market transactions and predictions (in USD billion) (based on images from [77]).

Figure 4

Magnetic interactions: (a) paramagnetic, (b) ferromagnetic, (c) antiferromagnetic, and (d) ferrimagnetic. Scheme of domains growing in a ferromagnet at: (e) zero magnetic field; (f) weak magnetic field; (g) strong magnetic field.

Figure 5

Hysteresis loop and domain growth of: (a) ferromagnet; (b) soft and hard magnetic materials hysteresis loop, respectively; (c) magnetic field dependence of the magnetization of a superparamagnet (reprinted from [78] ©2011 with permission from Elsevier).

Figure 6

(a) Schematic of operation of a solar panel and (b) a solar cell produced with Corning^® Willow^® Glass (reprinted from [115] © 2021 with permission from Willey).

Figure 7

Examples of flexible glass for photonics applications: (a) schematic fabrication of a smart window (reprinted from [131] © 2021 with permission from Wiley), (b) schematic of the fabrication and de-attachment process of healthcare device (available at [132] printed with permission CC BY 4.0), (c) waveguides of photonics for telecommunications application (reprinted with permission from [133] © The Optical Society).