“Samsung’s QLED technology played a crucial role in bringing quantum dots to the level of recognition needed for the Nobel Prize in Chemistry.”
— Taeghwan Hyeon, Seoul National University
Quantum dots have been on the forefront of show innovation over the previous decade, delivering a number of the most correct shade copy amongst present supplies. In 2015, Samsung Electronics paved the way in which for the commercialization of quantum dots with the launch of SUHD TVs — a breakthrough that moved past the usage of cadmium (Cd), a heavy steel historically utilized in quantum dot synthesis, by introducing the world’s first no-cadmium quantum dot expertise.
The educational world took discover. The profitable commercialization of cadmium-free quantum dot TVs not solely set a brand new course for analysis and growth but additionally performed a pivotal function within the awarding of the 2023 Nobel Prize in Chemistry for the invention and synthesis of quantum dots.
Following Part 1, Samsung Newsroom uncovers how Samsung has contributed to academia by means of groundbreaking advances in materials innovation.
▲ (From left) Taeghwan Hyeon, Doh Chang Lee and Sanghyun Sohn
Why Cadmium Was the Starting Point for Quantum Dot Research
“I was truly impressed that Samsung succeeded in commercializing a no-cadmium quantum dot display product.”
— Taeghwan Hyeon, Seoul National University
Quantum dots started attracting scientific curiosity within the 1980s when Aleksey Yekimov, former Chief Scientist at Nanocrystals Technology Inc., and Louis E. Brus, a professor emeritus within the Department of Chemistry at Columbia University, every revealed their researches on the quantum confinement impact and the size-dependent optical properties of quantum dots.
Momentum accelerated in 1993 when Moungi Bawendi, a professor within the Department of Chemistry on the Massachusetts Institute of Technology (MIT), developed a dependable methodology for synthesizing quantum dots. In 2001, Taeghwan Hyeon, a distinguished professor within the Department of Chemical and Biological Engineering at Seoul National University (SNU), invented the “heat-up process” — a way for producing uniform nanoparticles with out the necessity for size-selective separation. In 2004, Hyeon revealed a scalable manufacturing methodology within the educational journal Nature Materials — a discovery extensively thought to be a possible sport changer within the trade.
▲ Taeghwan Hyeon
However, these efforts didn’t instantly result in commercialization. At the time, quantum dots relied closely on cadmium(Cd) as a core materials — a substance recognized to be dangerous to people and designated as a restricted materials beneath the European Union’s Restriction of Hazardous Substances (RoHS) Directive.
“Currently, the only materials capable of reliably producing quantum dots are cadmium selenide (CdSe) and indium phosphide (InP),” defined Hyeon. “Cadmium selenide, the conventional quantum dot material, is a compound of group II and group VI elements, while indium phosphide is formed from group III and group V elements. Synthesizing quantum dots from group II and VI elements is relatively straightforward, but combining group III and V elements is chemically much more complex.”
▲ A comparability of cadmium-based quantum dots with ionic bonds and indium-based quantum dots with covalent bonds
Cadmium, a component with two valence electrons, kinds sturdy ionic bonds1 with components like selenium (Se), sulfur (S) and tellurium (Te) — every of which has six valence electrons. These combos lead to steady semiconductors, referred to as II–VI semiconductors, supplies which have lengthy been favored in analysis for his or her means to provide high-quality nanocrystals even at comparatively low temperatures. As a outcome, the usage of cadmium in quantum dot synthesis was thought of an instructional normal for a few years.
In distinction, indium (In) — an alternate…
