Premium
Universal Passivation Strategy for the Hole Transport Layer/Perovskite Interface via an Alkali Treatment for High‐Efficiency Perovskite Solar Cells
Author(s) -
Boonmongkolras Passarut,
Naqvi Syed Dildar Haider,
Kim Daehan,
Pae Seong Ryul,
Kim Min Kyu,
Ahn SeJin,
Shin Byungha
Publication year - 2021
Publication title -
solar rrl
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.544
H-Index - 37
ISSN - 2367-198X
DOI - 10.1002/solr.202000793
Subject(s) - passivation , perovskite (structure) , materials science , potassium , layer (electronics) , energy conversion efficiency , chemical engineering , alkali metal , inorganic chemistry , optoelectronics , chemistry , nanotechnology , metallurgy , organic chemistry , engineering
A passivation strategy for the perovskite/HTL interface is presented based on potassium acetate (K‐Ac). Since K‐Ac is soluble in both polar and nonpolar solvent, deposition of K‐Ac on top and bottom of perovskite is possible. With this advantage, the universality of potassium interfacial passivation at the HTL/perovskite interface applied to various configurations with various ranges of perovskite bandgap is reported. Regarding the p–i–n configuration, various materials characterizations reveal that a potassium passivation layer underneath perovskite modifies perovskite orientations, resulting in better charge transport and film properties. Furthermore, the potassium passivation layer shifts the valence band position of the HTL upward, which results in a better extraction of charges (holes) across the HTL/perovskite interface, thus improving the short‐circuit current density ( J sc ). The modification of the band alignment at the HTL/perovskite by the potassium interfacial passivation layer is confirmed in n–i–p devices with both WBG and CBG perovskites. Compared to reference solar cells without a passivation layer, an increase in J sc of approximately 1 mA cm −2 is observed in all cases, resulting in power conversion efficiencies of 19.42%, 20.06%, and 21.57% for WBG p–i–n, CBG p–i–n and n–i–p solar cells, respectively, demonstrating the wide applicability of the passivation strategy.