A Hydrogen-Bonding Strategy for Enhanced Perovskite Precursor Stability and Solar Cell Performance
발표자
임수환 (대구경북과학기술원)
연구책임자
최종민 (대구경북과학기술원)
초록
내용
In many works, the phase stability of formadinium (FA⁺) based perovskites has been enhanced by mixing additives containing methylammonium (MA⁺). However, a significant problem can be raised as the MA⁺ is readily deprotonated to MA0 because of its low pKa and the generated MA0 irreversibly reacts with FA⁺. This irreversible reaction triggers large organic carions as impurities hindering perovskite composition and crystallinity. This study shows that when 3-MBA is added to the perovskite precursor as an additive, the strong hydrogen bonding between FA⁺ and carboxylate group of deprotonated 3-MBA significantly improved the thermal stability of both the precursor and the perovskite film. Inverted perovskite solar cells with 3-MBA showed a high power conversion efficiency of 24.3%. Even after 1,740 hours at a high temperature of 85°C, they retained 98% of their initial performance, proving their remarkable thermal stability. The addition of 3-MBA improved solution stability, maintaining over 96% of their initial efficiency even after 140 days.