Structural Engineering for Efficient Transparent Vacuum-Deposited Perovskite Light-Emitting Diodes toward Intelligent Display

Perovskite light-emitting diodes (PeLEDs) have attracted significant interest in next-generation intelligent displays. Vacuum deposition is a promising method for integrating PeLEDs into intelligent displays due to its high manufacturability and easy pixelation, as proven in industrial organic light-emitting diode production. However, achieving spatially confined grains with optimized crystal remains challenging in vacuum-deposited perovskite. Here, a trisource coevaporation strategy is proposed to introduce MABr to form the MACs_1-PbBr₃ structure with carriers' spatial confinement and defect suppression as well. This approach enables PeLEDs to contain excellent external quantum efficiency (EQE), which is nearly 10-fold as the untreated device. Based on this, we realize the first reported vacuum-deposited transparent PeLEDs with double-sided emission and an amazing maximum EQE of 7.6% by replacing Al with an optimized Ag:Mg electrode. These transparent PeLEDs are integrated into a bifunctional intelligent display device with both accurate heart rate detection and imaging display, which exhibit bright patterned emission and accurate heart rate detection.