The Royal Swedish Academy of Sciences awarded the Nobel Prize in Chemistry 2023 to Moungi G. Bawendi (Professor at Massachusetts Institute of Technology, US), Louis E. Brus (Professor at Columbia University, US) and Alexei I. Ekimov (formerly Chief Scientist at Nanocrystals Technology Inc., US):
for the discovery and synthesis of quantum dots.
The Nobel Prize in Chemistry 2023 rewards the discovery and development of quantum dots, nanoparticles so tiny that their size determines their properties. These smallest components of nanotechnology now spread their light from televisions and LED lamps, and can also guide surgeons when they remove tumour tissue, among many other things.
Everyone who studies chemistry learns that an element’s properties are governed by how many electrons it has. However, when matter shrinks to nano-dimensions, quantum phenomena arise; these are governed by the size of the matter. The Nobel Laureates in Chemistry 2023 have succeeded in producing particles so small that their properties are determined by quantum phenomena. The particles, which are called quantum dots, are now of great importance in nanotechnology.
‘Quantum dots have many fascinating and unusual properties. Importantly, they have different colours depending on their size’, said Johan Åqvist, Chair of the Nobel Committee for Chemistry.
Physicists had long known that, theoretically, size-dependent quantum effects could arise in nanoparticles, but at that time it was almost impossible to sculpt in nano-dimensions. Therefore, few people believed that this knowledge would be put to practical use.
However, in the early 1980s, Ekimov succeeded in creating size-dependent quantum effects in coloured glass. The colour came from nanoparticles of copper chloride, and Ekimov demonstrated that the particle size affected the colour of the glass via quantum effects.
A few years later, Brus was the first scientist in the world to prove size-dependent quantum effects in particles floating freely in a fluid.
In 1993, Bawendi revolutionised the chemical production of quantum dots, resulting in almost perfect particles. This high quality was necessary for them to be used in applications.
Quantum dots now illuminate computer monitors and television screens based on QLED (quantum-dot light-emitting diode) technology. They also add nuance to the light of some LED lamps, and biochemists and doctors use them to map biological tissue.
Quantum dots are thus bringing the greatest benefit to humankind. Researchers believe that in the future they could contribute to flexible electronics, tiny sensors, thinner solar cells and encrypted quantum communication – so we have just started exploring the potential of these tiny particles.