From particles to films: production of Cs 2 AgBiBr 6 -based perovskite solar cells and enhancement of cell performance via ionic liquid utilization at the TiO 2 /perovskite interface

• Published in: Dalton transactions : an international journal of inorganic chemistry 2024-01, Vol.53 (3), p.1253-1264
• Main Authors: Öcebe, Arzu, Kaya, İsmail Cihan
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/D3DT02930A

Herein, Cs 2 AgBiBr 6 particles produced by the traditional super-saturation precipitation method were used as precursors to create Cs 2 AgBiBr 6 films by the gas-quenching process under ambient atmospheric conditions. These films were utilized as a light-absorbing layer in hole-transporting free perovskite solar cells (PSCs) with carbon electrodes. Furthermore, the incorporation of the 1-butyl-3-methylimidazole hexafluorophosphate (BMIMPF6) ionic liquid (IL) at the metal oxide electron transporting layer/perovskite interface resulted in enhanced crystallinity of the perovskite, forming large perovskite grains of up to 800 nm. However, it was discovered that establishing the optimal concentration for passivating surface defects takes precedence over encouraging the growth of larger perovskite grains. The utilization of the optimized BMIMPF6 concentration led to a remarkable increase in the power conversion efficiency (PCE) of the cell, with a boost of over 31% to reach 1.67%, when compared to the cell produced without the inclusion of the IL. Our findings underscore that the passivation of surface defects between the TiO 2 and perovskite layers holds more importance for enhancing the PCE of Cs 2 AgBiBr 6 -based perovskite solar cells than focusing solely on the perovskite morphology.