The Effects of Interfacial Recombination and Injection Barrier on the Electrical Characteristics of Perovskite Solar Cells

TL;DR

This paper theoretically investigates how interfacial recombination and injection barriers affect the electrical performance of perovskite solar cells, offering strategies to enhance their efficiency.

Contribution

It provides a detailed drift-diffusion model analysis of the effects of injection barriers and recombination on PSC performance, suggesting methods to improve efficiency.

Findings

Injection barriers cause carrier accumulation and electric field modification.

Zero electric field at specific voltages increases interfacial recombination.

Reducing injection barriers and recombination improves PSC efficiency.

Abstract

Charge carrier recombination in the perovskite solar cells (PSCs) has a deep influence on the electrical performance, such as open circuit voltage, short circuit current, fill factor and ultimately power conversion efficiency. The impacts of injection barrier, recombination channels, doping properties of carrier transport layers and light intensity on the performance of PSCs are theoretically investigated by drift-diffusion model in this work. The results indicate that due to the injection barrier at the interfaces of perovskite and carrier transport layer, the accumulated carriers modify the electric field distribution throughout the PSCs. Thus, a zero electric field is generated at a specific applied voltage, with greatly increases the interfacial recombination, resulting in a local kink of current density-voltage (J-V) curve. This work provides an effective strategy to improve the efficiency of PSCs by pertinently reducing both the injection barrier and interfacial recombination.