Development of colored perovskite solar cells using cholesteric helicoidal superstructures

Abstract

Perovskite solar cells (PeSCs) are promising candidates for building-integrated photovoltaics (BIPV) because of their excellent performance and processability. In this study, the first colored PeSCs that use liquid crystalline cholesteric phase-based reflective filters (ChRFs), which were inspired by the cuticle of a beetle, are developed. The reflective wavelengths, bandwidth, and reflectance of ChRFs are easier to modulate than those of reflective filters based on metals or oxides. Reflective wavelengths affect the hue, and they can be modulated by tuning the contents of a chiral dopant. The reflective bandwidth affects the power conversion efficiency, and it can be modulated by tuning the birefringence of the host liquid crystalline molecules. The reflectance also affects the chromaticity, and it can be controlled by modifying the simple optical design of the ChRF structure. ChRFs are suitable for large and flexible PeSCs because they are constructed using only organic components and wet processes.