Published January 1, 2024 | Version v1
Journal article Open

Incorporation Mechanism of Potassium in FAPbI<sub>3</sub> Perovskite Solar Cell Materials

  • 1. Marmara Univ, Phys Dept, TR-34722 Istanbul, Turkiye
  • 2. Yildiz Tech Univ, Fac Arts & Sci, Dept Phys, TR-34220 Istanbul, Turkiye
  • 3. Marmara Univ, Chem Dept, TR-34722 Istanbul, Turkiye

Description

We study the structural and electronic mechanisms of potassium (K+) incorporation in the FAPbI(3) perovskite layer. The K+ ions in FAPbI(3) perovskite solar cells lead to higher power conversion efficiency (PCE), lower trap density, and faster charge transfer. K+ eliminates the I-V hysteresis for 5% K-doped perovskite. Moreover, the phase stability is reduced by K+ incorporation. The enhancement in PCE and reduced stability are attributed to the passivation of deep-level charge traps and increased carrier mobility and lower phase change activation energy, respectively, and in all cases, K-FA antisite formation is revealed, by density functional theory (DFT) calculations, to be the main source. K-FA has reduced the electron-phonon coupling of charge transport and the activation energy barrier for the cubic-to-hexagonal phase transformation, which accelerates phase degradation. Our key findings will enable the future design and optimization of high-efficiency and stable mixed-perovskite solar cells.

Files

bib-e1d39a52-b5c1-4d8b-a299-a0613d923992.txt

Files (266 Bytes)

Name Size Download all
md5:fce3af5c20d82f2be75b666604cfbb47
266 Bytes Preview Download