Applications of perovskite materials in the display industry

This article was extracted from the Perovskite for Displays market report.

Given perovskites materials' unique optical properties, these materials are being intensively researched for both photovoltaic and display applications (as well as several others). In this article we will take a look into the possible application areas in the display industry that can benefit from perovskite materials.

Perovskite QDs

Perovskite-based QDs (PerQDs) are considered a viable Cd-free alternative for display applications, with high PL quantum yields, wide wavelength tunability and ultra-narrow band emission. The main advantages of PerQDs are:

Low cost
High performance
RoHS compliance (despite the lead content)

Perovskite hybrid organic-inorganic nanorods (HUJI)

Perovskite QDs may well be the first commercial application for perovskites. Several companies are already producing and selling perovskite quantum dots, and several companies already unveiled display prototypes that are based on PerQD films. It is expected that the first displays that adopt perovskite QD films will enter the market in the next few years ' maybe even as soon as 2022.

It is important to note that perovskite quantum dots have significant issues with stability - given their sensitivity to air, heat, light, and water. Researchers are fervently working on overcoming these weaknesses via new synthesis routes, novel encapsulation solutions and more. In addition, lead content remains an issue with many of the perovskite materials used for QDs, and while the quantity is low (and is claimed to adhere to the RoHS standard) it is still often an issue.

Perovskite LED

Current high-quality LEDs are based on direct bandgap semiconductors, but making these devices is no easy task because they need to be processed at high temperatures and in vacuum, which makes them rather expensive to produce in large quantities. Perovskites that are direct-bandgap semiconductors could be real alternatives to other types of direct-bandgap materials for applications like color displays, since they are cheap and easy to make and can be easily tuned to emit light of a variety of colors.

Researchers Fabricate Large-area Sky-blue PeLEDs image

Researchers have found that organometal halide-based perovskites (a combination of lead, organics and halogens that arrange into perovskite crystal structure in the solid state) could be very suitable for making optoelectronics devices, since they can be processed in solution and do not need to be heated to high temperatures. This means that large-area films of these materials can be deposited onto a wide range of flexible or rigid substrates. The perovskites also have an optical bandgap that can be tuned in the visible to infrared regions, which makes them very promising for a range of optoelectronics applications. These materials also emit light very strongly, which makes them very suitable for making LEDs. The light emitted by the perovskites can be easily tuned, which could make them ideal for color displays and lighting, and in optical communication applications.

However, a major obstacle that perovskites will have to overcome in order to be used in LED-type devices is that electrons and holes only weakly bind in perovskite thin films. This means that excitons (electron-hole pairs) spontaneously dissociate into free carriers in the bulk recombination layer, leading to low photoluminescence quantum efficiency (PLQE), high leakage current and low luminous efficiency. This obviously impairs perovskites' ability to create high-performance LEDs, and for perovskite materials to make a comparable impact in light emission, it is necessary to overcome their slow radiative recombination kinetics.

Simply put, researchers will have to find ways of effectively confining electrons and holes in the perovskite so that they can 'recombine' to emit light. Major progress is already being made in this field, and it seems that perovskites will indeed open the door to a low-cost, color-tunable approach to LED development, but the commercialization of such technology could take several years.

In an interesting research project, conducted at India's IIT Madrash research institute, the scientists were able to cure a natural white-emitting LED based on 'distorted' perovskite materials. This could provide to be an promising technology to enable white-emitting LEDs, useful for both displays and lighting projects.

Perovskite Lasers

Lasers are devices that stimulate atoms or molecules to emit light at particular wavelengths and amplify that light, typically producing a very narrow beam of radiation. The emission usually focuses on an extremely limited range of visible, infrared, or ultraviolet wavelengths. Laser is an acronym for 'light amplification by the stimulated emission of radiation'. Lasers are used in extremely diverse industries and applications, like optical disk drives, laser printers, barcode scanners, DNA sequencing instruments, fiber-optics, laser surgery and other medical applications, military and law enforcement devices and much more.

Nanowire perovskite lasers

As direct bandgap semiconductors, perovskites exhibit the unique optical properties of bandgap tunability, charge-carrier mobility, defect tolerance, photoluminescence quantum efficiency and power conversion efficiency. These properties make them promising light-emitting materials for high optical gain, low-threshold and multicolor laser applications. The fact that they can be fabricated from low-cost precursors via simple processes makes them attractive as well.
Lower dimensionality perovskite materials, like nanoplatelets, dots, disks, wires etc., can be tailored to be highly desirable for controlled lasing because of their optical cavities and feedback architectures.

Despite their promising features, there are several challenges, for example low exciton binding energy, environmental stability, and formation of trap states at the vicinity of grain interfaces, that need to be addressed when considering perovskite use in lasers. In that respect, 2D perovskites and triple/mixed cation perovskites appear to have potential, but commercialization will not likely begin for at least several years.

Perovskite materials for displays

This article was extracted from the Perovskite for Displays market report. The market report provides an introduction to the world of perovskites and the display industry, and covers everything you need to know about the current status of the market and industry.

This is a great guide if you're considering to adopt perovskite technologies in your display, or if you seek to enter the display market with perovskite materials - and also for anyone who wants to become an expert on next generation perovskite display materials.

Reading this report, you'll learn all about: