An improvement in un-Encapsulated perovskite solar cell’s environmental stability via introduction of an electrode interface layer

ABSTRACT

     Perovskite solar cells (PSCs) have shown power conversion efficiency (PCE) up to 25.5%, but they are still struggling with their poor environmental stability. We have improved the ecological stability of un-encapsulated PSCs via interface modification of the top metal electrode. We used CH₃NH₃PbI_3-xCl_x perovskite as the light absorber and Ag metal as the top electrode. The interface of Ag electrode was modified by introducing a thin layer of MoO_x/Al before Ag. We observed that MoO_x/Al interlayer before Ag imparts better stability to the devices than conventional Ag electrode only. We found that MoO_x/Al interlayer impedes the diffusion of oxygen and metal electrode into the perovskite film and considerably halts the device degradation upon being kept for about 350 h under laboratory ambient conditions (room temperature 25±2^oC and humidity 40±5%). This work mainly highlights the role of interfaces in PSCs degradation, and will help to address the stability issues in PSCs.

Graphical Abstract

KEYWORDS:

• Perovskite semiconductors
• perovskite shotovoltaics
• degradation mechanisms
• interface layers
• molybdenum oxide

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10667857.2022.2123759

Additional information

Funding

The work was internally supported by CSIR-National Physical Laboratory.