Science Daily March 22, 2024
The efficiency of p–i–n perovskite solar cells fabricated in air still lags behind those made in an inert atmosphere. An international team of researchers (China, USA-University of Colorado) introduced an ionic pair stabilizer, dimethylammonium formate (DMAFo), into the perovskite precursor solution to prevent the degradation of perovskite precursors. It inhibited the oxidization of iodide ions and deprotonation of organic cations, improved the crystallinity and reduced defects in the resulting perovskite films. They showed the generation of additional p-type defects during ambient air fabrication that suggested the need for improving bulk properties of the perovskite film beyond surface passivation. The efficiency of inverted p–i–n solar cells based on perovskite layers with 1.53-eV and 1.65-eV bandgaps fabricated under ambient conditions increased by 15–20%. They achieved a stabilized efficiency of 24.72% for the 1.53-eV cell, on a par with state-of-the-art counterparts fabricated in an inert atmosphere… read more. TECHNICAL ARTICLE