2, Institute of Chemical Sciences and Engineering, Laboratory of Photonics and Interfaces (LPI), Lausanne, , Swaziland
3, Physics Department, Science College, King Saud University, Riyadh, , Saudi Arabia
Perovskites solar cells (PSCs) showed a dramatic improvement in their power conversion efficiencies (PCE) from 3.8 to 22.7% within a short period and are approaching commercialization. Such an outstanding advancement was realized by simply tuning the composition of the perovskite absorber layer. This compositional diversity allows tailoring of their photophysical properties, such as absorption coefficient, photoluminescence yield, and charge-carrier dynamics, which critically influence the PCE of a resulting device. In this direction, we explored different sources of guanidinium cations to improve the photophysical properties, specifically, photoluminescence and charge-carrier dynamics of perovskite structures for their application in the fabrication of efficient solar cells. The effect of different sources of the guanidinium cations was systematically investigated by exploring various characterization techniques, including x-ray diffraction, scanning electron microscopy, steady-state absorption and emission spectroscopy, and time-resolved photoluminescence. The insights gained through these techniques helped us to understand the influence of guanidinium cations on the performance of PSCs. In my presentation, I will discuss structural, morphological and detailed photophysical characteristics of different perovskite films, and will correlate them with the photovoltaic performance of PSCs.