The discovery and development of quantum dots that have opened new frontiers for nanotechnology has been recognized today with the Nobel Prize in Chemistry, the Royal Swedish Academy of Sciences reported.
The winners are three scientists based in the United States: Moungi Bawendi, born in France, of the Massachusetts Institute of Technology; the American Louis Brus, from Columbia University in New York; and Alexei Ekimov, born in the former Soviet Union, of the company Nanocrystals Technology in New York.
They have been awarded "for the discovery and synthesis of quantum dots", according to the jury's verdict. The Nobel Committee in Physics specifies that quantum dots are "nanoparticles so small that their size determines their properties." It is "a new class of materials that are neither molecular nor large-scale."
Today, quantum dots "illuminate computer and television screens based on QLED technology. They also add hues to the light of some LED lamps, and are used by biochemists and doctors to map biological tissue," reports the Swedish academy. For example, "they can guide surgeons when removing tissue from a tumor."
Looking to the future, they are expected to allow the development of flexible electronic devices, thinner photovoltaic cells, nanosensors and quantum communication systems. Quantum dots, according to the academy, are already "providing great benefit to humanity" at a time when "we have only begun to explore the potential of these tiny particles."
In conventional chemistry, the properties of elements depend on their electrons, since it is through electrons that they react with other elements. But at nanometer scales, where the laws of quantum physics are manifested, the properties depend on quantum phenomena. Hence, quantum dots have become one of the most emblematic tools of nanotechnology.
"Quantum dots have many fascinating and unusual properties," said Johan Aqvist, chairman of the Nobel Committee for Chemistry. One of the most important is that "they have different colors depending on their size." It is this chromatic property that has allowed the first practical applications of quantum dots to be developed.
Other properties that depend on the size of quantum dots, and that could have practical applications in the future, include the melting temperature or the reduction potential (i.e., the tendency to lose electrons in a reduction-oxidation reaction).
It was Alexei Ekimov, a Russian physicist living in the US, who laid the foundations for this field of research. In pioneering experiments carried out in the 1980s, he demonstrated that it is possible to cause crystal color changes through quantum effects in copper chloride nanoparticles. Until then, it had been considered infeasible to control particle size-dependent quantum effects.
The chemist Louis Brus complemented Ekimov's work by demonstrating in the following years that it was possible to control size-dependent quantum effects in particles floating freely in a fluid.
Finally, the chemist Moungi Bawendi, born in Paris to a family from Tunisia and living in the United States since childhood, discovered a way to produce quantum dots in large quantities and of high quality, which opened life to using them widely. scale in consumer products. The quantum dots market amounted to €3.8 billion in 2021.
"The discovery of quantum dots was an important step in the development of nanoscience, and inspired many chemists to dedicate themselves to this interdisciplinary field," highlights the Nobel Committee for Chemistry. "This year's laureates played a central role in establishing the capabilities [of nanotechnologies] and provided the seeds for the growth of the rich field of nanoscience."
The Nobel Prize in Chemistry is traditionally the third to be made public and is announced on Wednesday of the first week of October. On Monday, the Medicine Award was awarded to Katalin Karikó and Drew Weissman for the development of messenger RNA vaccines, which were key to mitigating the impact of the covid pandemic. Yesterday, Ferenc Krausz, Pierre Agostini and Anne L'Huilier received the Physics award, who have laid the foundations for the new field of attophysics, which allows us to visualize how electrons move in times of trillionths of a second.
Tomorrow the Literature prize will be announced, on Friday the Peace prize and on Monday the 9th, the Economy prize.
