Researchers from China's Southern University of Science and Technology, by simultaneously measuring the electroluminescence-photoluminescence, have identified the presence of leakage electrons in QD-EL devices, which leads to the discrepancy of the electroluminescence and the photoluminescence roll-off.

The researchers then developed a single photon counting technique, the enables them to detect the weak photon signals and thus provides a means to visualize the electron transport paths at different voltages. By reducing the amount of leakage electrons, the researchers developed a QD-EL device with an internal power conversion efficiency of over 98%.

Korean QD producer Hansol Chemical, has conducted an analysis on some of TCL's QLED panels, and concluded that in fact these panels do not contain any quantum dots. Hansol commissioned SGS and Intertek to actually perform the study, on TCL's C755, C655 and C655 Pro models.

Hansol says that TCL's TVs do not contain any indium or cadmium at all, which proves the TVs do not contain quantum dots. TCL responded by saying that the TVs do in fact contain Cadmium, although perhaps at a very trace amount not detected by SHS and Intertek. TCL further says that the method used is not sufficient to detect the exact content of Cadmium.

Researchers at Daegu Gyeongbuk Institute of Science and Technology (DGIST), Ulsan National Institute of Science and Technology (UNIST), and the Institute for Basic Science (IBS) have developed a new method, called double-layer dry transfer printing, to create highly efficiency QD-EL displays.

The researchers say that with the double-layer dry transfer printing technique, the light-emitting and electron-transferring layers of the device can be transferred onto a substrate simultaneously, which reduces interfacial resistance in the device, which facilitates electron injection and the control of leakage charge transport during the fabrication process. The researchers, by minimizing the leakage current, managed to increase the EQE of the QLED device to 23.3%, up from around 5% that is achieved with normal dry transfer printing. 

During Displayweek 2024, Samsung demonstrated its latest display prototypes, focusing mostly on flexible OLEDs, and QD-OLEDs.

The company also showed a 18.2" 3200x1800 (202 PPI) 250 nits QD-EL display, that was produced using an inkjet-printing process, based on cadmium-free QDs.

TCL CSoT demonstrated a 14" 2.8K inkjet-printed QD-EL display, that offers 30-120Hz VRR refresh rates and a 85% BT2020 color gamut. The impressive display won SID Displayweek's People's Choice Award.

TCL's CEO gave a keynote speech at Displayweek, saying how this is an early-stage technology that still has a lot of challenges before it can be commercialized - mainly the lifetime of the blue material. To encourage collaboration and innovation, TCL CSOT announced the Blue Star Project with a $1 million prize to incentivize collaboration and accelerate breakthroughs in QD-EL technology.

Researchers from Korea's Institute for Basic Science, led by Professor KIM Dae-Hyeong, published a new article in Nature that details intrinsically stretchable quantum dot LEDs. 

The researchers say that using current technology, making stretchable light-emitting devices results in poor luminous performance. The researchers now produced the intrinsically stretchable QD-LEDs using a mechanically soft and stretchable emissive layer consisting of a ternary nanocomposite of colloidal quantum dots, an elastomeric polymer and a charge transport polymer.

Samsung Display recently decided to move around 500 engineers from its large-area QD-OLED business unit to its small-and-medium sized AMOLED business unit. This move could signal a change in SDC's confidence in its QD-OLED technology.

A new article at OLED-Info discusses the technology and market challenges of QD-OLEDs, the recent activities in the display industry and market - and states that Samsung may be not invest further in its QD-OLED technology.

DSCC says that the demand for QD materials in the display industry is growing, and the market will grow to $100 million in 2024. It will continue to grow and reach $122 million in 2027. 

The main application is in LCD displays (color conversion), but materials used in QD-OLED's (by Samsung Display) is growing and accounts for 31% of the market (in the chart above DSCC notes QD-OLEDs as QD-CC). Production of QD-OLED panels is limited (SDC's total capacity is for around 2 million panels per year) but the material usage is large compared to QD-LCDs.

Sharp was demonstrating two new QDEL prototype at CES 2024. The first was 12-inch in size (you can see this in the video below), and the second a 30-inch prototype (Sharp did not allow to take photos/videos of the larger display).

Sharp did not disclose much about the display, or any commercialization plans. This seems to be an early-stage development. We do know that Sharp is using QD materials produced by Nanosys (SHOEI), and that the display is produced on an IGZO (Oxide-TFT) backplane.