Molecular Interlayers in Hybrid Perovskite Solar Cells

Abstract

Organic–inorganic hybrid perovskite solar cells (PSC) are promising third‐generation solar cells. They exhibit good power conversion efficiencies and in principle they can be fabricated with lower energy consumption than many more established technologies. To improve the efficiency and long‐term stability of PSC, organic molecules are frequently used as “interlayers.” Interlayers are thin layers or monolayers of organic molecules that modify a specific interface in the solar cell. Here, the latest progress in the use of interlayers to optimize the performance of PSC is reviewed. Where appropriate interesting examples from the field of organic photovoltaics (OPV) are also presented as there are many similarities in the types of interlayers that are used in PSC and OPV. The review is organized into three parts. The first part focuses on why organic molecule interlayers improve the performance of the solar cells. The second section discusses commonly used molecular interlayers. In the last part, different approaches to make thin and uniform interlayers are discussed.

Defect Activity in Lead Halide Perovskites

“…by setting up Pb-O chemical bonds [46] .The deposition of interlayers is one strategy for protecting perovskite layers against atmosphere related degradation improve device stability. [44,45] Moisture resistance can be improved with deposition of hydrophobic layers, however, poor wettability of hydrophobic compounds over the perovskite surface usually results in poor coverage. We have demonstrated the application of PEO, a hydrophilic polymer, as an interlayer for perovskite photovoltaic devices.…”

Caesium for Perovskite Solar Cells: An Overview

“…[33][34][35][36][37] The core component of this solar cell is the perovskite active material, bearing ag eneric structure ABX 3 ,i nw hich Ai samonovalent cation (like methylammoniumC H 3 NH 3 + or MA, formamidinium CH 2 (NH 2 ) 2 + or FA,C s + ,R b + ), Bs tands for Pb II or Sn II and Xf or Io rB r. [38][39][40][41][42] The outstanding optoelectronic properties of perovskites, characterizedb yh igh mobility and absorption co-efficient, long-balanced carrier diffusionl ength and low-exciton bindinge nergy,j ustify the current success of this photovoltaic technology. [43][44][45][46][47] Severalr eview articles have been published on different strategies to improve the performance of lab-scale PSCs. [48][49][50][51][52][53][54][55][56][57] As it is typical for novel technologies, [58][59][60][61][62] research in the field of PSCs is currently focusedo no vercoming important issues, starting from the difficulty of reproducing high power conversion efficiency (PCE) values when the devicea rea is increaseda tt he module level.…”

Triarylphosphine Oxide as Cathode Interfacial Material for Inverted Perovskite Solar Cells

“…Examples of interfacial engineering are the modification of the band offsets at the perovskite/extraction layer interface to favor charge extraction, as well as decreasing interfacial nonradiative carrier recombination. Through this methodology, the long‐term stability of the devices has also been improved . Interfacial engineering can be used to modify the electronic properties of the n‐contact stack of the devices as well.…”