Near-infrared electroluminescent devices based on colloidal HgTe quantum dot arrays

Crystalline 4.6 nm HgTe quantum dots, stabilized by 1-thioglycerol ligands, were synthesized by wet chemical methods. Room-temperature photoluminescence spectra of the dots, both in solution and as solid arrays, exhibited near-infrared emission. Light-emitting devices were fabricated by deposition of quantum dot layers onto glassindium tin oxide (ITO)3,4-polyethylene- dioxythiophene-polystyrene sulfonate (PEDOT) substrates followed by top contacting with evaporated aluminum. Room-temperature near-infrared electroluminescence from 1 mm2 ITOPEDOTHgTeAl devices, centered at ~1600 nm, with an external quantum efficiency of 0.02% and brightness of 150 nWmm2 at 50 mA and 2.5 V was achieved.