Colloidal Silicon Quantum Dot-Based Cavity Light-Emitting Diodes with Narrowed and Tunable Electroluminescence

Abstract

Luminescent colloidal silicon quantum dots (SiQDs) have been explored as alternatives to metal-based QDs for light-emitting diodes (LEDs) because of the abundance and biocompatibility of silicon. To date, the broad electroluminescence (EL) bandwidth (> 100 nm) and blue-shifting of EL at high applied voltages of SiQD-LEDs have been outstanding challenges that limited competitive spectral purity and device stability. Herein, we report the fabrication and testing of SiQD-LEDs that incorporate a Fabry-Pérot cavity that exhibit a narrow spectral linewidth as low as ca. 23 nm. The presented devices also provide spectral and visual stability from +4 V to +8 V, as well as spectral tunability.