Hydrogen Bond-Assisted Dual Passivation for Blue Perovskite Light-Emitting Diodes

Despite progress in developing green, red, and near-infrared perovskite light-emitting diodes (PeLEDs), blue PeLEDs have lagged behind due to defects and poor carrier injection in solution-processed perovskite films. This study introduces dual-passivation additive diphenylphosphinamide (DPPA) into perovskite films, shown through density functional theory calculations and experiments to be an effective passivator. The phosphine oxide group coordinates with unsaturated lead ions, while the amino group forms hydrogen bonds with halide ions, reducing defect density and ion migration. DPPA-modified blue quasi-two-dimensional PeLEDs reached an external quantum efficiency of 12.31% at 486 nm, with operational lifetime extended by 32%.