Revolution of Perovskite

Currently, lead halide perovskite materials involving organic-inorganic hybrids and all-inorganic ones have attached more and more attention for their adhibition in photovoltaic devices, because of the unique properties like high light absorption coefficient, tunable bandgap, long carrier lifetime, and carrier diffusion length. In addition, it can be clearly seen that perovskite materials have unusual magnetic properties and excellent electronic properties. Herein, the structure of B-site substituted perovskite oxides are reviewed, and magnetic properties of A₂BʹB″X₆ are controlled by modifying their cations, such as magnetic order, leading to a wide range of possibly and interesting useful new materials. We review the perovskite manganite with a strongly correlative electronic system, and the strong interactions within electron results in sophisticated electronic properties and magnetic properties. Electronic structure and unique characteristics of halide perovskites such as the special Pb orbit and the grain boundaries of electrically benign are surveyed. What’s more, the suitable and excellent optical properties of kinds of perovskites with mixed compounds for solar cells, light-emitting diodes, and other applications are addressed.

Perovskite oxide materials, an important inorganic crystal class with the general formula of ABO₃ exhibit a broad spectrum of functional properties such as dielectric, ferroelectric, piezoelectric, and magnetic properties, which have promising applications in modern microelectronics. Due to their structural simplicity and flexibility, many desirable properties can be tailored by appropriate chemical substitutions at the A- and/or B-sites of perovskite structure. Therefore, the perovskite-type oxides are probably the most studied family of oxides in the past century. Many preparation methods using solid, liquid, or gas phase precursors have been developed to synthesize perovskite oxide materials. This chapter gives a comprehensive summary of the preparation methods of perovskite-type oxide materials with a wide range scope from bulk perovskite oxide ceramics to perovskite oxide nanopowders, and to perovskite 1D, 2D, and 3D oxide nanostructures.

Due to exceptional light absorption and superior carrier transport properties, solution-processable hybrid perovskites have realized outstanding performance on solar cells and photodetectors in recent years. As hybrid perovskites contain high atomic number lead and halide elements, they are greatly suitable for X-ray detection and imaging purposes. Here, we present ongoing research in perovskite-based X-ray detectors and low-dose images, which are highly valuable for medical applications. In addition, magnetic oxide perovskite La_0.7Sr_0.3Mn_0.98Ti_0.02O₃ nanoparticles with magneto-temperature response, as well as double-perovskite L₂NiMnO₆ for adsorption of bovine serum albumin will be introduced. Moreover, in vitro cell proliferation studies reveal low cytotoxicity and promising biocompatibility of perovskite CaTiO₃ in cellular environments, thus justifying its benign functions in osseointegration and osteoblast adhesion. This chapter could advance the roles of perovskite materials in biomedical applications.

Hybrid organic–inorganic perovskites materials have gained a lot of attention due to its unprecedented growth within a decade in optoelectronic device applications. However, stability of the hybrid perovskite materials especially under sunlight and heat remains one of the major threats for potential commercialization. There are numerous reports on improved photo and thermal stability of the perovskite materials, but the ultimate goal is not yet achieved. The migration of ions in these materials under illumination and in the presence of heat is the root cause of photo and thermal instability. In this chapter, some of the major pathways and mechanism related to the ion migration is discussed. The presence of ionic defects/vacancies is responsible for ion migration. However, the activation energy barrier for the migration of ions/vacancies depends on multiple factors, such as nature of ions, crystal structure and migration pathways. Some of the proposed mechanism of vacancy-mediated ion migration is also discussed. The migration of ions can be quasi-reversible as some of the migrated ions get stuck at the grain boundary or at the perovskite/charge transport layer interface. The charge transport in these materials therefore gets modulated with the ionic conductivity. As the perovskite active layer gets degraded, the ionic conductivity increases, mainly due to the increased vacancies. There have been some experimental evidences that the activation energy barrier gets reduced upon heating due to lattice expansion. Therefore, the choice of perovskite is important as the lattice expansion can be minimized by some combinatorial approach of mixed halide as well as mixed cationic perovskite materials. It is evident from the experiment as well as from the first-principles density-functional theory that the crystal structure with fewer defects not only has superior optoelectronic properties but also has improved stability under adverse environmental condition. Therefore, the key research of perovskite-based optoelectronic devices should be focused on the synthesis of defect-free large crystals with reduced ion migration.

Perovskite-type materials are oxide compounds with a growing interest in different disciplines because of the wide range of ions and valences that can be tailored in a simple structure, resulting in oxide compounds with various physical and chemical properties of technological application. Perovskite materials are rather simple to synthesize because of the flexibility of the structure to diverse chemistry. Actually, properties of technological interest of perovskites are photocatalytic activity, magnetism, or pyro–ferro and piezoelectricity, catalysis, and energy storage. In this book chapter, the usage of perovskite-type oxides in batteries is described, starting from a brief description of the perovskite structure and production methods. In addition, a description concerning the latest advances and future research direction is presented. Experimental studies are presented in this chapter as an example of the synthesis and application of perovskite materials in batteries.

This chapter presents a summary of the design and development of perovskite-based functional materials for the application in perovskite solar cells (PSCs) and dye-sensitized solar cells (DSSCs) as the light absorbers, the electron transportation materials, and the photoelectrodes. The importance of increasing the power conversion efficiency (PCE) and the long-term operational stability is explained, and the operational principles and the functions, advantages, and requirements of the perovskite-based key functional materials for PSCs and DSSCs are described. Some design strategies to enhance the PCE and durability of perovskite-based PSCs and DSSCs are presented including the functional doping, morphology control, interfacial engineering, coupling and the defect control, etc. Some challenges and future research topics in this dynamic field are also presented in order to provide some useful guidelines for the future development of perovskite-based materials for photovoltaics (solar cell) applications. This chapter is interesting and useful to a broad readership in the various fields of PSCs, DSSCs, electrochemistry, photochemistry, photocatalysis, electrocatalysis, and so on.

Electrocatalysis-based technologies are central to enabling the vision of a sustainable energy future. One major challenge is to develop nonprecious, high-efficient electrocatalysts that can promote the electrocatalytic processes. Perovskite materials have recently been extensively studied as alternative electrocatalysts to noble metal-based materials owing to their low cost, tunable structure, and high catalytic activity. This chapter discusses perovskite materials in electrocatalysis for several important reactions, including the oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction. The electrocatalytic mechanisms are first introduced to offer a fundamental understanding of the electrocatalysis occurring on the surface of perovskite catalysts. Following this is a detailed description of the rational design of perovskite materials toward efficient electrocatalysis. Several activity descriptors for theoretically guiding the catalyst design are presented while many other practical parameters that can influence the catalyst behavior are also highlighted. In addition, concerns for the catalyst stability under realistic electrochemical conditions are expressed. In an effort to realize global energy sustainability, several key applications of perovskite materials in electrocatalysis-related energy devices, for example, metal–air batteries and water electrolyzers, are presented, with an emphasis on how to enable the widespread penetration of these energy technologies.

Today’s exigency to furnish more sustainable energy requires materials and expedients with enhanced or even new functionalities. Harvesting solar energy using stable, cheap, and environmentally friendly materials, for solar water splitting and dye degradation, is an attractive approach. The present chapter is focused on the recently reported perovskites oxides for the photocatalytic applications such as dye degradation, CO₂ reduction, and water splitting under UV or visible light irradiation. Material preparation and characterization are two essential parameters; former is to get materials with desired structure and physicochemical property, and latter gives the information of the textural structures and properties of the synthesized photocatalysts. In this regard, the present chapter provides an insight into information of preparation and photocatalytic application of selected ABO₃-based photocatalysts. It opens up a new viable approach for the synthesis of highly efficient perovskite-type photocatalysts for environmental remediation and energy production. The present chapter is organized into five sections: (1) a brief introduction to photocatalysis, (2) methods to tailor the photocatalytic properties of semiconductor photocatalysts, (3) a short overview of perovskite oxides as photocatalysts, (4) recent developments in enhancing the photocatalytic activity of perovskite materials, and (5) conclusions and insights.

Hybrid organic–inorganic semiconductors, usually referred to as perovskites, are low-cost semiconductors that have interesting optoelectronic properties and the potential to revolutionize several electronic devices. In most cases, these are usually composed out of alternating organic and inorganic parts and can be synthesized as three or lower dimensional semiconductors, thus exhibiting interesting quantum phenomena arising from the inorganic network’s dimensionality decrease. These quantum phenomena are observable at room temperature for the hybrid low-dimensional systems due to extra dielectric confinement occurring on the electrons and holes due to the dielectric contrast between the inorganic and organic parts. These perovskites have been attracting intense attention for future optoelectronics and electronics due to their exceptional attributes, including high carrier mobility, chemically adjustable spectral absorption and luminescence range, 100% internal quantum efficiency as well as the simplicity and affordability of fabrication rendering. All the above features render these hybrid organic–inorganic materials as one of the most exceptional and market-competitive optoelectronic materials for device application such as photovoltaics, light-emitting diodes (LEDs), lasers, sensors, transistors, and more. Here, we review the hybrid organic–inorganic halide perovskites, the progress over the years, and their application in new technologies related to such electronic devices.

In order to achieve photovoltaic technologies’ commercial availability, high power conversion efficiency, low cost, large area, low toxicity, and long lifetime are crucial attributes. In recent years, perovskite materials have emerged as one of the most-studied photovoltaic materials for its high-performance and cost-effectiveness. However, the development of protocols to industrialize the perovskite technology still faces several severe challenges. In this chapter, we summarize the challenges and obstacles of perovskite material research from four aspects. For successful commercialization, the high stability and long-term lifetime is primary and essential. Second, Lead toxicity is also an important obstacle for practical application due to its threat to human health Third, for improving the fabrication repeatability, hysteresis and relevant measurement standards is discussed. Finally, the capacity to fabricate large-area and flexible modules based on recently reported state-of-the-art perovskite solar cells are also discussed.