Degradation mechanism and addressing techniques of thermal instability in halide perovskite solar cells

So far, halide perovskite solar cells (PSCs) have been known as the important devices having significant growing efficiency, despite of their not so impressive stability compared to other types of solar devices. Among the stability research, thermal stability of halide PSCs is still a challenge for their commercialization. Therefore, in this study, the degradation mechanism on thermal instability has been explored using different ways including morphological analyses and transient photocurrent measurements, the transient photoconductivity, dielectric and noise measurements and low-frequency noise measurement. The strategies suppressing the thermal instability have been explained basing on the aspects of the electron transport layers (ETLs) like doping of the ETL and employing double layers; light absorption layers such as grain passivation; hole transport layers (HTLs) which may include use of dopant free HTL and graded hybrid structure of layers as well as the 2D perovskites. Therefore, this review is expected to contribute towards development of perovskite solar cell materials and promote practical applications.