The Polymer Society of Korea

Abstract

Quantum dot light-emitting diodes (QLEDs) offer color purity and solution processability; however, the performance of blue devices remains limited by charge imbalance and nonradiative recombination losses. Here, we report a solvent-engineering strategy employing a high-boiling aliphatic additive in a TFB-based hole transport layer (HTL). The additive selectively dilutes loosely packed polymer regions while preserving aggregated domains, suppressing nonradiative decay and enhancing radiative recombination in the HTL. Steady-state and time-resolved photoluminescence analyses show that the reduced nonradiative loss enhances Förster resonance energy transfer (FRET) from the HTL to the quantum dot emissive layer, shifting exciton generation toward the quantum dots. Consequently, blue QLEDs show improved performance, with the external quantum efficiency increasing from 9.8% to 14.1%.  This work demonstrates that solvent engineering of HTLs improves exciton utilization in QLEDs.