Preface

This book provides guidance for researchers to better understand the properties of perovskite and the latest development of applications. It introduces the kinds of perovskite materials, crystal structures, physical and chemical properties, preparation methods, and recent advances regarding applications in different fields.

The authors who collaborated in this book have summarized present advances of perovskite oxides and halide perovskite in certain fields related to environment conservation and energy utilization, as well as their experience of perovskite-related research. The book contains nine chapters, organized in three sections that cover important research aspects regarding the whole perovskite system.

The first section consists of an introductory chapter prepared by the editor for the purpose of presenting a brief background on perovskite materials. It describes that perovskite is a material with an ABX3 structure, which includes perovskite oxide and hybrid perovskite such as Ba2XOsO6 (X = Mg, Zn, Cd) and Cs2AgBiBr6. In this section, the crystal structures and morphologies of perovskite materials have been systematically introduced. Subsequently, we discussed the preparation methods of materials and devices. The synthesis techniques and application of perovskite oxides are discussed in detail in a separate chapter. Through the introduction of physical characteristics, it can provide help for the construction of high-performance devices. In view of the exotic properties of perovskite, the applications and development of perovskite materials in different fields including environment protection and energy utilization are illustrated.

The second section discusses environment conservation and energy utilization. Specifically, this section highlights the progress of using perovskite materials for solar cells and focuses on elucidating a few challenges of these materials in various aspects. And then, different functionalities in perovskites are reviewed from abatement of pollutants to energy conversion and storage. Take a NOx removal as an example, this section overviews recent research on development of novel perovskite-based catalysts for NOx removal from diesel engine exhaust gases. This section provides precise concentrations on the over-all related of perovskite materials and explores the synthesis methods and morphologies. Finally, this section reveals the significant tasks and outlooks of perovskite photocatalytic applications.

The third section presents other applications including the quantum dot LED, resistive random-access memories, and half-metallic ferromagnetic and spintronic applications. The self-issue of perovskite materials and the solution to this problem are proposed in this section, which provides a strategy for constructing high performance devices.

The editor expresses his thanks to all the participants in this book for their valuable contributions and to Ms. Nina Kalinic Babic for her assistance in finalizing the work. Acknowledgment to the IntechOpen staff members responsible for the completion of this book and other publications for free visible knowledge.

**II**

**Section 3**

for QD-LED Application

*Jai Singh and Ranveer Kumar*

*by Jiaqi Zhang and Wubo Li*

*by Sajad Ahmad Dar*

Other Applications of Perovskite **115**

**Chapter 7 117**

**Chapter 8 137**

**Chapter 9 157**

Lead-Free Hybrid Perovskite Light-Harvesting Material

*by Rajan Kumar Singh, Neha Jain, Sudipta Som, Somrita Dutta,* 

Perovskite Materials for Resistive Random Access Memories

(X = Mg, Zn, Cd): Important Candidates for Half-Metallic

Osmium Containing Double Perovskite Ba2XOsO6

Ferromagnetic and Spintronic Applications

**He Tian** Tsinghua University, China

**1**

Section 1

The Overview

of Applications and

Prospects of Perovskite

Materials

Section 1

The Overview of Applications and Prospects of Perovskite Materials

**3**

**Chapter 1**

Applications

**1.1 Solid phase synthesis**

**1.2 Sol-gel method**

**1. Perovskite structure and synthesis**

Introductory Chapter: Perovskite

Perovskite is considered one of the most promising materials of the twenty-first century. In the past few decades, the perovskite has attracted broad attention and made great progress in energy storage, pollutant degradation as well as optoelectronic devices due to its superior photoelectric and catalytic properties. All materials with ABX3 structure are collectively referred to as perovskite materials, which can be simply divided into inorganic perovskite and organic-inorganic hybrid perovskite. The tolerance factor is usually used to indicate the structure of perovskite. Each ion radius in perovskite oxide should satisfy the following equation: t = ((rA + rO))/ (√2(rB + rO)), where rO, rA, and rB are the radii of respective ions A, B, and oxygen elements. So far, various perovskites, such as Ba2XOsO6 (X = Mg, Zn, Cd), Cs2AgBiBr6, and CH3NH3PbX3 (X = Cl, Br, I), have been synthesized and used in different fields. For example, perovskite oxides play a pivotal role in half-metallic ferromagnetic, spintronic applications, energy storage, and pollutant degradation, while the halide perovskite is used for LEDs and photodetectors. Currently, diverse preparation methods have been developed for the synthesis of perovskite with different dimensions. For instance, solid phase synthesis method and sol-gel method are used for synthesizing perovskite oxide and hydrothermal method for halide perovskite.

Solid phase synthesis is a traditional preparation to obtain perovskite oxides by evenly mixing two or more kinds of metal salts and pressing them into sheets. After calcining at a certain temperature, this material can be acquired by grinding calcined sample. To study its magnetism, Yuan et al. prepared the perovskite oxide Y1−xGdxFeO3 (0 ≤ x ≤ 1) with good crystal structure by solid phase method [1]. This preparation process has the advantages of simple production process and low cost,

Organometallic compounds or inorganic metal salts as precursors are hydrolyzed or alcoholized to form sol and are finally condensed to form gel. After heat treatment, the required oxide powder is obtained. The commonly used gels include ethanol, ammonia, polyvinyl alcohol, citric acid, etc. Taguchi et al. synthesized LaCoO3 with small particle size by using ethylene glycol and citric acid as gel [2]. Besides, the effects of different calcination temperatures on the properties of

and as-prepared materials have high mechanical strength.

materials were also studied by Toro et al. [3].

Materials and Advanced

*Xiangshun Geng, He Tian and Tian-Ling Ren*

## **Chapter 1**
