Efficient Green-Emitting Aminophosphine-Derived InP-Based Quantum-Dot LEDs Enabled by Photo-cross-linked Hole Transport Layer Engineering

Abstract

Cadmium-free indium phosphide (InP) quantum dot light-emitting diodes (QLEDs) are promising for next-generation displays, but high-quality green-emitting InP quantum dots (QDs) are still commonly synthesized using highly reactive tris(trimethylsilyl)phosphine. Here, we employ tris(dimethylamino)phosphine as a safer phosphorus precursor to prepare InP/ZnSexS1–x/ZnS QDs. Optimizing the intermediate alloy shell yields green QDs with a photoluminescence quantum yield of 96.1% and a full width at half-maximum of 36.5 nm. A photo-cross-linked PF8Cz:BPO6 hole transport layer improves film compactness and hole transport, while an ultrathin polyvinylpyrrolidone interlayer regulates excessive electron injection. The optimized QLEDs achieve a maximum external quantum efficiency of 10.5% and a peak luminance of 16,219 cd m–2. This work demonstrates a practical strategy for improving the electroluminescent utilization of aminophosphine-derived InP QDs through coordinated material and interface engineering.