Recent Progress and Challenges of Electron Transport Layers in Organic–Inorganic Perovskite Solar Cells

Taewan Kim,Seulki Song,Jongchul Lim

doi:10.3390/en13215572

Abstract

Organic–inorganic perovskites are crystalline light absorbers which are gaining great attraction from the photovoltaic community. Surprisingly, the power conversion efficiencies of these perovskite solar cells have rapidly increased by over 25% in 2019, which is comparable to silicon solar cells. Despite the many advances in efficiency, there are still many areas to be improved to increase the efficiency and stability of commercialization. For commercialization and enhancement of applicability, the development of electron transport layer (ETL) and its interface for low temperature processes and efficient charge transfer are very important. In particular, understanding the ETL and its interface is of utmost importance, and when this understanding has been made enough, excellent research results have been published that can improve the efficiency and stability of the device. Here, we review the progress of perovskite solar cells. Especially we discuss recent important development of perovskite deposition method and its engineering as well as the electron transport layer.

Highlights

Perovskite solar cells, since Miyaska et al reported the organic–inorganic perovskite solar cells [1], have been considered to be a promising candidate as a future energy source because of their potential for very low cost and high efficiency
After solution-processed perovskite material is applied to the solid state solar cell, the efficiency is accelerated, which changed the history of photovoltaics [2,8]
With the rapid growth of efficiency, over 25% of high-efficiency perovskite solar cell is reported [9], it reached a similar efficiency level to copper indium gallium diselenide (CIGS) solar cells [10], and researches are trying to reach the efficiency of commercial monocrystalline silicon cells

Summary

Introduction

Perovskite solar cells, since Miyaska et al reported the organic–inorganic perovskite solar cells [1], have been considered to be a promising candidate as a future energy source because of their potential for very low cost and high efficiency. Energies 2020, 13, 5572 selection and engineering are very important to achieve high-efficiency, and highly stable perovskite solar cells. For mass production or flexible device applications, n-type material and engineering are required that can be prepared at low temperatures and provides high efficiency and stability as high as high-temperature processes n-type material. Due to this importance, most of noticeable development in perovskite solar cells were done by engineering perovskite and electron transport layer. TiO2 or SnO2 has been used as an n-type material in high-efficiency devices, and studies have been conducted to increase the efficiency and stability of devices through small changes in materials or interface engineering. We will explore the noteworthy achievements in hybrid perovskite solar cells in ETL and its engineering and look at the direction we are going forward

Materials

Structure and Engineering

Findings

AlAldoped doped