Tailoring perovskites for solar cells and light emission applications

Abstract

Perovskites have shown great potential for applications in solar cells and light emission. Recently, two-dimensional (2D) perovskites have started making waves in the research field. With their superior tunability and stability, they show great potential for a wide variety of applications. However, their performance in photovoltaic and optoelectronic applications are mediocre. In this report, a 2D perovskite with a novel functionalised organic component is exposed to high pressures in hopes of improving its performance for both solar cell and light emission applications. It was found that the inorganic lattice was quite sensitive in pressure, experiencing contraction and distortion in pressures of less than 5 GPa. This caused obvious changes in optical properties at relatively low pressures applied. This is due to the soft organic cations being very bendable and hence flexible, allowing for room to withstand pressure and instead, causing the inorganic lattice to undergo the effects of compression more severely.

However, although the pressure-treated sample retained most of it optical properties, it did not retain most of its structural properties. Only the ammonium constituents in the organic cation was retained. This implies that most of the changes in the perovskite crystal structure is irreversible, and that other bonds were actually responsible for the similar pressure-treated optical properties.