Influence of Anti-Solvents on the Performance of Cesium Bismuth Iodide Perovskite Solar Cells

Abstract

In this paper, the influence of anti-solvents on the properties of cesium bismuth iodide (CBI – Cs3Bi2I9) perovskite solar cells (PeSCs) that were dripped with different anti-solvents, i.e., isopropanol, chlorobenzene (CB), and toluene during the spin-coating process was evaluated. Scanning electron microscopy images visually depicted the presence of extremely flat and homogeneous film with highly compactness for the Cs3Bi2I9 fabricated with isopropanol compared to other anti-solvents. A strong absorption band was observed at around the wavelength of 500 nm for all the CBI films, and we found that the maximum absorption percentage reached as high as 85%, while the current-voltage measurement showed that the CBI film fabricated with isopropanol showed twenty-one times increment than CB, in terms of power conversion efficiency and short circuit current density. Our findings suggest a further improvement of CBI film morphology by the anti-solvent for enhanced morphology and better solar cell performance in the future.