How scientists found a new way to synthesise quantum dots
The world of science just got a little brighter—literally! Three chemists, Moungi G. Bawendi, Louis E. Brus and Aleksey Yekimov, discovered efficient ways of synthesising quantum dots nanoparticles, including some of its exciting properties, and subsequently received the Nobel prize 2023 in honour of their discoveries.
Quantum dots are semiconductor nanocrystals, that are typically a few nanometres wide, that have characteristics that can potentially shape our future. These nanoparticles are molecules, containing many atoms (primarily Silicon or Carbon), arranged in a certain way, such that quantum effects enhance their properties. They are often called ‘artificial atoms’, because they have properties similar to single atoms, except they are huge --roughly 10 times bigger!
Examples of some of the amazing properties exhibited by quantum dots is the fluorescent light they emit upon excitation. When UV light is shined at the quantum dots, depending on their size, they emit different ranges of colours as shown in the figure below.
This property in particular is what led to the invention of the QLED TV. An array of quantum dots are arranged in such a way that the nanocrystals are excited through UV light, to emit bright and vibrant colours, which are then used to form pictures and videos. The quantum dots are exceptionally efficient when compared to LEDs. In a typical LED TV, the LEDs produce pure --boring-- white light, that is then passed through a filter, which, as the name suggests, filters the desired colour. However, quantum dots are stubborn; they produce only one colour, which relaxes the use of filters, and thereby allows the projection of sharp and clear colours.
But TVs are just the beginning! The QLED TV has been around for a long time; to be precise, the first specimen was introduced to the market in 2013. Moreover, nanoparticles were discovered four decades ago, so what is it that the Nobel laureates discovered? The three scientists have worked on the synthesis of these nanoparticles which resulted in greater cost-efficiency, navigating their role in the industry. Furthermore, the award was given for the discovery of additional properties exhibited by these quantum dots, which have surprised the scientific community. For example, the quantum dots, on top of cool lighting effects, have the ability to catalyse chemical reactions in physical and biological systems --again saving money. Quantum dots have also been used to save lives; the researchers have employed light-emitting quantum dots and other nanoparticles to illuminate tumours in tissues!
These groundbreaking discoveries have not only expanded the scientific understanding of quantum dots, but also opened the door for more questions and potential applications for shaping our future.
Moynihan, Tim. “What Are Quantum Dots, and Why Do I Want Them in My TV?” WIRED, 19 Jan. 2015, www.wired.com/2015/01/primer-quantum-dot.
“Chemistry Prize.” NobelPrize.org, www.nobelprize.org/prizes/chemistry.