Drastic influence of substituent position on orientation of 2D layers enables efficient and stable 3D/2D perovskite solar cells


Gunes U., Yaylali F. V., Gozukara Karabag Z., Gao X., Syzgantseva O. A., Karabag A., ...More

Cell Reports Physical Science, vol.4, no.5, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 4 Issue: 5
  • Publication Date: 2023
  • Doi Number: 10.1016/j.xcrp.2023.101380
  • Journal Name: Cell Reports Physical Science
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Directory of Open Access Journals
  • Keywords: 3D/2D perovskite solar cells, novel organic 2D cations, stability, tunneling effect
  • Middle East Technical University Affiliated: Yes

Abstract

The lack of long-term stability and reproducibility of perovskite solar cells (PSCs) is the main roadblock preventing their successful commercialization. 3D/2D PSCs are one of the most prominent ways to address these issues. Various salts that are mostly based on phenyl ethyl ammonium iodide (PEAI) have been utilized to grow a 2D perovskite layer on 3D perovskites. Herein, we report the effect of substituting the methoxy (-OMe) group at the ortho (o), meta (m), and para (p) positions on PEAI salts. Photoluminescence and time-resolved photoluminescence show that o-OMe-PEAI-treated surfaces achieve reduced defect densities and nonradiative recombination rates compared with the other analogs. Devices with PCEs over 23% are achieved for o-OMe-PEAI-based 3D/2D PSCs, and the enhanced performance is attributed to the favorable formation energy and desired vertical orientation according to the density functional theory (DFT) analyses. Finally, the unique orientation of the o-OMe-PEAI-based 2D perovskite results in significantly enhanced long-term, moisture, and thermal stability.