If you do not wipe up spilled coffee immediately, it will leave a stain with darker edges than the others. This phenomenon is called the coagulation effect (Coagulation effect in the field of quantum points). Using this principle, the POSTECH research team recently developed a new method for sorting nanoparticle-sized (QD) quantum dots. This new and simple approach (Coagulation effect in the field of quantum points) accelerates the development of display panels with a resolution 20 times higher than traditional.
POSTECH research team – led by Professor Junsuk Rho from the Department of Mechanical Engineering and Chemical Engineering, Professors HangJin Jo and Moo Hwan Kim from the Department of Advanced Nuclear Engineering, and Professors from the Department of Mechanical Engineering Taeyang Han from the Department of Advanced Nuclear Engineering and Jaebum Noh, Ph.D. candidate at the Department Mechanical Engineering – The QD field was created with an event that occurs when the slurry evaporates. Suspension refers to a liquid in which solid particles, such as mud water, ink, or paint, are dispersed and suspended.
QDs of several nanometers can closely monitor fluid flow. Just as a drop of liquid leaves a coffee stain on the side of the cup when the suspension evaporates by QD, the particles automatically collect in certain areas, such as the edge of the drop caused by capillary flow.
Many attempts have been made to use this feature, but it is difficult to obtain light suitable for performances. The cost of this product is also high because QD is printed directly on the substrate using expensive equipment. To overcome this limitation, the researchers used a V-shaped structure to control QD in the form of very small pixels during the suspension evaporation process. As the liquid is poured and evaporated, the QD is collected in an internal V-shaped tip and collected there.
The results showed that the brightness of the QD pixels produced in this way was 20 times brighter than in the control group and showed a high uniform rate of more than 98%.
“The home appliance industry has recently used QD in color filters on TVs for a clear and natural picture,” said professors Junsuk Rho and HangJin Jo. Using the QD pixel array method developed in this study, light QD pixels are simply produced by spraying the suspension without expensive equipment, thus reducing production costs.
The research was published in ACS Applied Materials and Interfaces.
