Interface Engineering for Highly Efficient and Stable Planar p‐i‐n Perovskite Solar Cells

Abstract

Organic‐inorganic halide perovskite materials have become a shining star in the photovoltaic field due to their unique properties, such as high absorption coefficient, optimal bandgap, and high defect tolerance, which also lead to the breathtaking increase in power conversion efficiency from 3.8% to over 22% in just seven years. Although the highest efficiency was obtained from the TiO2 mesoporous structure, there are increasing studies focusing on the planar structure device due to its processibility for large‐scale production. In particular, the planar p‐i‐n structure has attracted increasing attention on account of its tremendous advantages in, among other things, eliminating hysteresis alongside a competitive certified efficiency of over 20%. Crucial for the device performance enhancement has been the interface engineering for the past few years, especially for such planar p‐i‐n devices. The interface engineering aims to optimize device properties, such as charge transfer, defect passivation, band alignment, etc. Herein, recent progress on the interface engineering of planar p‐i‐n structure devices is reviewed. This review is mainly focused on the interface design between each layer in p‐i‐n structure devices, as well as grain boundaries, which are the interfaces between polycrystalline perovskite domains. Promising research directions are also suggested for further improvements.

High‐Performance Perovskite Solar Cells with Enhanced Environmental Stability Based on a (p‐FC6H4C2H4NH3)2[PbI4] Capping Layer

“…This is because of the formation of too thick 2D perovskite capping layers with poor charge transport properties. [65,66] The corresponding incident photon conversion efficiency (IPCE) was carried out to testify the photon energy response of the devices. [ 2D capped 3D perovskite film achieves higher V OC of 1.126 V, a J SC of 22.80 mA cm −2 , and an FF of 0.80, leading to an improved PCE of 20.54%.…”

Novel Surface Passivation for Stable FA0.85MA0.15PbI3 Perovskite Solar Cells with 21.6% Efficiency

“…After TPFPB passivation, the J sc and FF increase obviously, which is mainly attributed to efficient hole extraction and passivation of surface traps. Meanwhile, the hysteresis behavior in PSCs w TPFPB passivation was obviously suppressed (Figure S8 and Table S4, Supporting Information); the reduced trap‐state density at the perovskite/HTL interface is the main reason for the eliminated hysteresis effect in PSCs . Figure b shows external quantum efficiency (EQE) spectra of PSCs wo/w TPFPB passivation, where it is clearly shown that the photoelectron collection in the wavelength range of 500–800 nm was enhanced by the TPFPB passivation, indicating that a higher J sc was generated in PSCs w TPFPB passivation.…”

Interface Engineering in n‐i‐p Metal Halide Perovskite Solar Cells

“…Previous reviews have indicated the importance of interface engineering in MHP solar cells, but a thorough understanding of the relationship among interface modification layers, roles, and characterization methods is lacking. In this review, we highlight the roles of interface engineering in n‐i‐p MHP solar cells and summarize characterization methods and recent research advances in interface modification based on various classifications.…”