Samsung Electronics announced that the quantum dot (QD) sheets used in its QD TVs received certification for compliance with the Restriction of Hazardous Substances (RoHS) directive and has been verified to contain no cadmium by the global certification institute, Société Générale de Surveillance (SGS).

Samsung says that it has actively developed QD materials and technologies, and has secured around 150 patents for the technology.

According to reports from Korea, Samsung Electronics has decided to accelerate the development of its QD-EL display technology. Working together with its affiliate companies, Samsung aims to commercialize QD-EL displays within the next few year.

The reports suggests that Samsung Electronics is working closely with SAIT (Samsung's advanced research institute) and Samsung Display. QD-EL displays are similar to OLED displays, but they use quantum dots as the emitter material. This is the first display technology that uses the QD's electroluminescence, rather than the photoluminescence, used in color conversion for QD-LCDs, QD-powered microLEDs, and QD-OLEDs.

Apple launched its latest laptops, the M4 MacBook Pro models, and according to DSSC the new displays adopt a red quantum dot film for the first time.

Up until now, Apple used red KSF phosphor films, but the QDs offer more accurate and vivid colors as the emission spectrum is narrower. In the past Apple opted for KSF because this technology does not use any Cadmium and it is lower in cost. Apple's new QD films are Cadmium-free.

Material developer Avantama announced that it is set to sell its entire perovskite QD IP portfolio. The company says that it has managed to bring the technology to market-readyness level, and is looking for a company that will bring it to market. 

Ocean Tomo Transactions (a part of J.S. Held) will be representing Avantama in the sale of its pQD IP portfolio. The company has developed over 220 IP assets, which includes patents on processes, compositions, formulations, films, and devices for the commercialization of semiconductor nanoparticle and quantum dot inks and films.

A couple of months ago we reported that Korean QD developer Hansol Chemical commissioned SGS and Intertek to test some of TCL's QLED TVs, finding that these do not in fact contain any Cadmium or Indium. Hansol  has now filed a complaint with the Fair Trade Commission (FTC) in the US against TCL, saying that it falsely advertised its TVs as QD-LED TVs.

In its FTC complaint, Hansol mentioned three TCL TV models: C755, C655 and C655 PRO. This will be interesting to watch.

Researchers from Sungkyunkwan University developed a source material for the inorganic hole transport layer of QD-EL devices. The researchers say that the new material significantly enhances the brightness and stability of emissive QD displays.

The researchers say that currently used organic HTL materials suffer from low conductivity and thermal instability. The new material is a standard HTL doped by defect-controlled nickel oxide-magnesium oxide alloy and treated with magnesium hydroxide. Using the new material, the EQE of the QD-EL device increased to 16.4%. The doping and treatment lowered the hole conductivity of the hole transport layer and suppressed the hole extraction process from within the quantum dots, thereby enhancing the device efficiency to a level comparable to existing technologies.

Samsung Display announced that it has developed a new technology that can recover around 80% of the quantum dots ink used in its QD-OLED production process. The recovered inks is refined through advanced synthesis technology that revives its purity and optical properties. The company will apply this technology, to its process and it is expected to save around 10 billion Won (around $7.3 million USD) each year in QD materials cost.

It turns out that even though the QD layers are inkjet printed, there is still significant waste of materials, as around 20% of the total QD ink used in the process remains in the nozzles and cannot be used. This new technology will enable SDC to make its QD-OLED panels more competitive with other large-area panel technologies.

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 SGS 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.