In the current study, an incisive review of the recent noticed advances implemented to improve the net efficiency of PSCs through using metal oxide nanoparticles as the charge transport materials is delivered, focusing on the architectures as well as the different fabrication pathways based on solution processes for metal oxides as transport materials for PSCs. Usually, organic materials are utilized as the charge transport materials, but the synthesis and cost of these materials requires researchers to find alternative materials. The inorganic metal oxide materials are deemed promising substitutional materials for charge transport process in PSCs. The obtained efficiency as well as the stability of the studied cells in the proposed work are highlighted; matching these metal oxide materials energy levels with the valence band of perovskites can develop the net efficiency of the assembled cells. Finally, the economic feasibility of PSCs using these different metal oxide materials is discussed.

Crystalline properties and the microstructure of matter are among the most important factors that determine its efficiency in various applications. The atomic level in the three different phases (macroscopic, micro, and nanoscale) is the primary criterion for which the material is chosen on the basis of the specified applications. As for the case of perovskite materials, they have many types—singles, doubles, and layered—and the stability of the materials depends on these types. For this reason, the discussion in this chapter revolves around the materials and the importance and applications of nano-perovskites, especially in the energy sector, from energy conversion such as fuel cells to energy storage such as lithium batteries. The most important information has been reviewed regarding perovskites at the nanoscale. Furthermore, the efficiency of perovskite has been proven in different energy applications, in addition to its most important characteristics that affect its efficiency in application.

Perovskite solar cells (PSCs) have attracted many researchers due to their excellent power conversion efficiency (PCE) of 25.2%, and can be a substitution for silicon solar cells as future technology. The efficiency of PSCs has been enhanced from 3.8% to 25% and has evolved to be better technology than copper indium gallium selenide or cadmium telluride solar cells. The properties of perovskite materials such as high ion mobility, long carrier charge lifetime, and long carrier charge diffusion length enable the materials to be utilized as a light-absorbing layer in solar cells. Perovskite solar cells have surprising intrinsic properties like excellent charge transport, dielectric constants, and less exciton binding energy with high device performance. The power conversion efficiency (PCE) of perovskite solar cells depends upon the specific functions of each layer composition and architecture. The device architecture of PSCs can influence different parameters like open circuit voltage, fill factor, short circuit current, and PCE of the device. The energy band gap, light absorption of specific wavelength, performance, and stability can be varied/changed by regulating the positons of different sites (A, B, or X site) in perovskite crystal structure. The improvement of different functions of layer structure influences PSC performance. The synthesis methods of perovskite also influence cell performance. Enhancement of PSC performance can be achieved by improving different synthesis methods by adopting compositional or defect or crystal growth engineering. The role of electron and hole transport layer is also important for movement of charge carriers toward respective electrodes. Therefore, selection of electron and hole transport material influence the performance of solar cell. The study of physical parameters like charge transport, ion migration, charge recombination, polarization, and defects in crystal are important to understand the operational mechanism of perovskite layer and transport layers. The main issues of PSCs are their stability and toxicity. The stability of perovskite crystal and transport layer under different environmental conditions is also important for performance of PSC and its commercialization. This chapter contains a discussion on the progress of perovskites as a light absorption material for third-generation solar cells, material modification, fabrication methods, device architecture, and stability of PSCs. The chapter will consider basic physics like exciton formation, point defects, ion migration, ferroelectric properties, charge transport, charge recombination, and other physical properties in PSCs for enhancing device performance.

Perovskite materials became the most successful and effective low-cost energy products for various applications including optoelectronic, magnetic, sensing, and photonic devices. Perovskite is a naturally occurring mineral of calcium titanate (CaTiO3). CaTiO3 was found by the Russian mineralogist Lev Sinovsky in 1839, and materials of the same form of crystal structure were called perovskite material (structure) in the same way as those of CaTiO3. The terms “perovskite” and “perovskite structure” are frequently used interchangeably. ABX3, where A and B are cations with A greater than that of B, and X is anionic oxides (O2 −) or halogens (F−), is the general chemical formula used for the description of perovskites. Various perovskite-type oxides have been studied in detail for their electrical conductivity responses to changes in humidity for their applications as humidity sensing. Exploration and investigation of the humidity sensors and morphology of porous perovskite compounds continue to provide new and inventive findings. Perovskites have been used to fabricate transducers, capacitive humidity sensors, and microdevices.

In this chapter, some aspects of crystal structure of organic-inorganic perovskite materials have been presented. The problem of organic-inorganic hybrid layered halide perovskite was extensively discussed and illustrated very clearly, since it is closely related to the core of this chapter. Comparison with double perovskite was briefly mentioned. In the second part of this chapter, the recent applications of lead halide hybrid perovskites have been considered in general with the focus on the most interesting subjects, namely photovoltaic and solar cells, optoelectronics and electronics as highly selected titles of present investigations. Five optoelectronic properties—light-emitting diodes (LEDs), lasers, photodetectors, water splitting, and field effect transistors (FETs)—were explained in detail. Near the end of this chapter, a future vision was outlined.

Perovskite structures possess excellent properties such as optical, electrical, and high absorption coefficient. Perovskite materials have been utilized as efficient light absorbers for perovskite solar cell (PSC) applications. The PSC was developed in 2009 and decent power conversion efficiency of 3.1% was achieved. Later, numerous efforts were made by materials scientists and physicists to increase the power conversion efficiency (PCE) of PSCs, leading to a PCE having been reported and certified at more than 23%. The developed PSCs are considered cost-effective and high performance energy conversion devices among next-generation solar cells. In this chapter, basic principles and components of PSCs are discussed with emphasis on the stability of the cells. The current challenges and future perspectives are reviewed.

This chapter considers up-doped and Eu3 +-doped gadolinium zirconate (GZO) phosphors that were prepared by a conventional method. Photoluminescence properties were observed for GZO and Eu3 +-doped GZO; in addition, color rendering index (CRI) and correlated color temperature (CCT) values are calculated. The structural analysis of prepared phosphor was studied by X-ray diffraction (XRD) analysis. The morphology of prepared phosphor was investigated via the scanning electron microscopic (SEM) technique. Pure GZO phosphor shows a broad emission centered at 475 nm, and doped phosphor shows a broad emission peak centered at 475 nm and a sharp line emission centered at red (611 nm) due to electric dipole transition (5D0-7F2). Some additional peaks centered at 629 and 651 nm are due to 5D0-7FJ (J = 2,3) electric dipole transition. The synthesized phosphor was monitored under UV light and it demonstrates an intense white emission after the UV light is removed, meaning that the afterglow properties were found in the sample. Pure GZO shows an intense blue emission, and this may be useful for opto-electronics applications for solid-state lighting; doped GZO phosphor also shows overall white light emission monitored by CIE and under UV light, and this may be useful for WLEDs.

This chapter mainly focuses on the development of various hybrid organic-inorganic perovskite (HOIP) composites. It also describes the different mechanisms to develop the HOIPs composites. Several classes of HOIPs like single crystals, polycrystalline, and thin films are investigated for dielectric, ferroelectric, piezoelectric, pyroelectric, electrochemical, and photovoltaic applications. In particular, the graphite/SiO2-CH3NH3PbCl3 − xBr showed electrochemical behavior and was used as an electrochemical drug sensor. Methylammonium lead (MAPbI3) was used for high-performance and inexpensive solar cells.

Nowadays, the development of storage systems and renewable energy sources are in high demand. One of the most prominent storage systems is supercapacitors (SCs). The greatest challenge is to develop SCs displaying extreme energy and power densities. Owing to its higher thermal stability, high conductivity, great specific capacitance, valuable reversibility, highly reversible faradic reaction, excellent pseudo-capacitive behavior, and high rate capability, ruthenium as metal oxide is extensively studied and very promising for supercapacitor applications. In addition, carbon-based materials, particularly graphene oxide (GO) and reduced GO (RGO), have also been utilized as effective materials in SCs because of their excellent mechanical and electrical traits. It has been established that the combination between Ru-based perovskites and RGO or GO are beneficial for SCs with the highest performances. This chapter describes advancements in high-performance SCs based on Ru-based perovskites/RGO or GO composites.

Solution processed all-inorganic trihalide perovskite nanocrystals are potential materials for the fabrication of future generation optoelectronic devices. However, the surface of the perovskite nanocrystals should be encapsulated to prevent degradation. Because of their stability under ambient conditions, nanocomposites of perovskite nanocrystals have been intensively researched for display applications. Perovskite nanocrystals dispersion or growth in a polymer matrix imparts structural stability and influences the optical properties, preventing effects such as halide migration. Developing flexible, high-performance lighting devices through perovskite nanocomposites will need to be evaluated on the compatibility of nanocrystals within the polymer matrix. Research in this area has escalated, but specific attention is required to address the practical challenges. This chapter discusses the current developments in the field of preparation and processing of nanocomposites of pure inorganic perovskite nanocrystals. Organic ligands, fabrication methods, encapsulating compounds, solvents, and other deposition procedures affecting the performance and stability of nanocomposites are discussed.