Colloidal quantum dots (QDs) have been extensively investigated as promising alternative visible emitters to traditional inorganic bulk phosphors and organic luminescent materials owing to their tunable emission wavelengths, narrow spectral bandwidths, excellent photoluminescent (PL) quantum yield, and solution-process compatibility [1–4]. Since the first demonstration of colloidal QD light emitting diodes (QLEDs) in 1994 [5], the performance of monochromatic QLEDs has been significantly improved including luminance, external quantum efficiency (EQE), and device stability by optimizing the device structures and material properties [6–10]. Although monochromatic QLEDs show excellent performance such as maximum luminance up to 23,040, 218,800, and 2250cdm−2, and EQE of 7.3%, 5.8%, and 1.7% for red (R), green (G), and blue (B) QLEDs, respectively [8], it is still challenging to obtain high-resolution full-color QLED displays [2,11,12].