Polymer strategies in perovskite solar cells

Abstract

Since their emergence in 2013, perovskite solar cells have reached remarkable efficiencies exceeding 22%. Such rapid development of this technology has been possible, in part, due to the feed of ideas from previous research in organic photovoltaics (OPVs) and light emitting diodes (OLEDs). This comprehensive review discusses the various polymer strategies that have led to the success of perovskite devices: from hole and electron transporting materials to polymer templating agents. This review further covers how these strategies potentially serve to overcome the two major obstacles that stand in the way of global implementation of perovskite solar cells; stability and J-V curve hysteresis. Through reference and comparison of OPV, OLED, and perovskite technologies, we highlight the need for a unified approach to establish appropriate control systems and ageing protocols that are necessary to further research in this exciting direction.

Limitations of a polymer-based hole transporting layer for application in planar inverted perovskite solar cells

“…If we keep in mind the well-known fact that the mobility of a perovskite absorber far exceeds that of PTAA and other organic HTLs, this leads to the conclusion that the transient decay and resulting charge extraction trends are governed by the mobility of the PTAA lm. [61][62][63][64] Therefore, it is reasonable to pinpoint PTAA as an obstacle to efficient charge extraction, rather than the interface with MAPI. Interestingly, even though the previously discussed ATR results did not indicate any severe oxidative degradation of PTAA, it seems that structural alterations even under shorter UV irradiation noticeably affect its hole extraction capabilities.…”

Two‐Dimensional Conducting Polymers: Synthesis and Charge Transport

“…This approach certainly gets the benefits of thickness control and short reaction time . Examples include polyaniline (PANI), polypyrrole, and poly‐(3,4‐ethylenedioxythiophene) (PEDOT), which demonstrated long‐range order, high crystallinity, robust mechanical strength, and excellent conductivity …”

Electron‐Transport Materials in Perovskite Solar Cells

“…Most polymer applications have solved the moisture problem by providing barrier properties or serving as template agents. However, the stability of devices was tested only in storage but not under operation conditions, so it is necessary to explore the effects of other stress factors (UV, temperature, mechanical stress) on the overall device stability . Meanwhile, most organic ETLs must be very thin due to their poor conductivity, which may impede their real applications.…”