# Efficient AgInGaS-based QLEDs and full-color displays via uniform silver vacancy distribution

## TL;DR

A new method for making AgInGaS quantum dots with uniform silver vacancies improves display performance and enables full-color QLEDs.

## Contribution

A multistep temperature control strategy enables uniform silver vacancy distribution in AgInGaS quantum dots.

## Key findings

- Red, green, and blue AIGS QDs achieved high photoluminescence quantum yields and narrow emission.
- QLEDs fabricated using these QDs showed external quantum efficiencies of up to 13.2%.
- Full-color QD pixel arrays with 2032 pixels per inch resolution were demonstrated.

## Abstract

AgInGaS (AIGS) quantum dots (QDs) are promising for displays due to their narrow full width at half maximum (FWHM) and tunable emission. However, nonuniform silver vacancy (VAg) distribution causes emission broadening and hinders device performance improvement. Here, we present a multistep temperature control strategy that precisely regulates reaction temperature to control nucleation, cation exchange, and defect reconstruction, thereby enabling uniform VAg distribution in AIGS QDs. Simultaneously, we construct a dual-layer shell structure (AgGaS2/GaSx), which efficiently passivates surface defects. The synthesized red, green, and blue AIGS QDs achieve photoluminescence quantum yields (92.6, 98.5, and 53.3%) and narrow FWHMs (32, 29, and 21 nm). On the basis of these materials, we fabricated red, green, and blue QD light-emitting diodes that demonstrate external quantum efficiencies of 13.2, 8.0, and 2.9%. Moreover, the interfacial confinement self-assembly strategy enables the fabrication of full-color QD pixel arrays with resolutions up to 2032 pixels per inch, further highlighting the potential of AIGS QDs for near-eye displays.

Multistep temperature control enables uniform VAg distribution in AIGS QDs for efficient QLEDs and full-color displays.