Improved efficiency and stability of perovskite solar cells based on clays

Halide perovskites have attracted great attention from many researchers recently, particularly for their excellent optoelectronic properties in applications such as photovoltaic solar cells. In recent years, perovskite solar cells (PSCs) have made great progress with a power conversion efficiency exceeding of 26% comparable to single-crystal silicon solar cells, but the stability issue still limits commercialization. PSCs allow the absorption of large amounts of photons compared to Si solar cells and have a thin layer. This provides a great advantage in terms of cost. Another important advantage of perovskite is its long diffusion path and high carrier mobility. The degradation of PSCs is mainly due to oxygen, moisture, light and heat caused by external environmental factors. In this study, we use natural clays instead of synthetic porous materials. The clays were selected according to their chemical structure and solvent dispersibility. Montmorillonite, laponite, halloysite and Na-bentonite were used in this research. Significant improvements were observed using clays as scaffold. The improvement in efficiencies were observed around 5% with montmorillonite, 13% with halloysite and 7% with laponite in comparison with reference cell. These results show that those clays can be alternative natural, non-toxic and low-cost materials as scaffold layer in PSCs.