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This content will become publicly available on September 3, 2026

Title: Effective Selection and Targeted Passivation for Different Defect Types by Ammonium Salts in Perovskite Solar Cells
Abstract The optimal selection of alkyl chains and halogen ions in ammonium salts for addressing specific defect types in perovskite films remains unclear, although ammonium salts emerged as a promising strategy to enhance the performance of perovskite solar cells (PSCs). Herein, four ammonium salts are introduced with different alkyl chain types and halogen ions to passivate perovskite films. Branched‐alkyl chain ammonium salts exhibited superior passivation effects compared to linear‐alkyl chain salts, with the alkyl chain structure having a more significant impact on device performance than the halogen ion component. In addition, DFT calculations are performed to investigate which defect types in perovskite films are most effectively passivated by different alkyl chain types and halogen ions in ammonium salts. Branched‐alkyl chain ammonium salts demonstrated superior passivation effects on VPband VFAdefects in perovskite films compared to linear‐alkyl chain salts, while exhibiting similar passivation effects for VIdefects. PSCs passivated with tert‐OAI achieved an impressive efficiency of 25.49%, with a Vocof 1.19 V, a Jscof 25.40 mA cm−2, and an FF of 84.34%. This work highlights a targeted ammonium salt passivation strategy tailored to address different defect types in perovskite films, accounting for variations in perovskite composition and fabrication environments.  more » « less
Award ID(s):
2326788 2418390 2242467 2423854
PAR ID:
10640363
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Energy Materials
ISSN:
1614-6832
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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