Recently, researchers at Koc University in Istanbul, Turkey, used quantum dots suspended in liquids to create relatively efficient LEDs. The researchers pointed out that when quantum dots are taken out of the liquid and then fixed in a solid form, the efficiency of quantum dot emission is reduced.
This loss of efficiency is referred to as the matrix material effect. Therefore, researchers can eliminate the matrix material effect by simply incorporating the liquid into the LED. RGB and GB white light have luminous efficiencies of up to 64 lm / W and 105 lm / W.
According to their theoretical calculations, liquid QD-LEDs can achieve luminous efficiencies of more than 200 lm / W. The researchers also pointed out that the optical properties of the fluid medium can be changed by replacing the medium, and the spectrum can also be modified by controlling the mixing ratio of the fluid.
They demonstrate that the use of liquid-based quantum dots can increase luminous efficiency by more than 50% due to the inhibition of matrix material effects. Second, as the quantum yield of quantum dots increases, the ratio of the number of emitted photons to the number of absorbed photons increases significantly, resulting in more efficient color conversion and higher white LED efficiency.
They also fine-tuned the color conversion spectrum to bring the peaks closer to the peak of the eye sensitivity function. This additional fine tuning has a high luminous efficiency of optical radiation.
Researchers have published the results of the study at Optica, the journal of the Optical Society.