Tribenzyl Organic Cations Carried Multidentate X-Type Lewis Soft Base for High-Performance Foldable Perovskite Light-Emitting Diodes.

Lead-halide perovskite nanocrystals (PNCs) exhibit significant potential for advancing foldable perovskite light-emitting diodes (F-PLEDs) due to their discrete crystalline morphology, bright emission across an extensive color gamut, and remarkable color purity; however, their progression remains in the early stages with the concerns of inadequate performance and mechanical instability. This study proposes a ligand strategy employing tribenzyl organic cation (tribenzylamine, TBA) carried multidentate X-type Lewis soft base (sodium acid pyrophosphate, SAPP) to address the challenges above simultaneously. Specifically, the use of multibranched aromatic ligands considerably improved the adhesion force between PNCs and adjacent layers, enhancing mechanical stability during folding, while the control sample shows deleterious cracks.