The subatomic particle trio: the proton, the electron, and the neutron, all of which are responsible for each element working exactly as it should. All of which is the exact reason why each substance has its specific properties and not others. As far as everyone knows, these three tiny particles dictate properties and contribute to the behavior of elements and substances.
However, there is a limit to how much influence these particles have over other substances. All things have limits, a person’s temper, an asymptote in calculus, even temperature. Subatomic particles are no exception. What’s ironic about this particular limit though is that the only thing that can best these remarkable intricacies of chemistry is what takes its most humbling feature to a whole new level: size.
When something is shrunk to a size that mimics the size of these subatomic particles (albeit a bit larger), they effectively lose their impact on a substance’s properties. In that (quantum) realm, size dictates the properties, behaviors, and colors of a substance (known as a quantum dot). Yes, you heard (or I suppose read) that right: the colors of a substance are determined by its size. But first, let’s review how all of this came to light.
It was early into the 1980s, the technological advancement race was fast progressing. Alexei Ekimov, a Russian physicist, stumbled upon a ‘eureka’ discovery, perplexed about how the color of these quantum dots can change depending on how much they were shrunk. This massive discovery at the time prompted Louis Brus (an American physical chemist), only a few years later, to tirelessly invest countless hours into discovering the next big revelation: the size of a quantum dot can even dictate its properties, defying the natural rules of chemistry (where subatomic particles dominate the property and behavior scene of substances). But, this research was all theoretical: there was no application to it. After all, how can you take these transformative particles and turn them into something that could be used?
In 1993, Moungi Bawendi, an American-Tunisian-French chemist, took that question to the battlefield as he discovered the way to chemically engineer these particles in a near-perfect way, enabling these quantum dots to be responsible for lighting up your computer monitors, illuminating your TV, adding the shades of gray to LED lamps, and even play a role in modern medicine through allowing doctors to map out biological tissue.
In 2023, three decades since the last of these three great scientists made these discoveries, they were all awarded the Nobel Prize of 2023 in Chemistry. It’s ironic: the smallest things oftentimes become the biggest, we just don’t realize it yet. From finding out that color changes by size to discovering how properties are impacted by shrinking or expanding these quantum dots to making them adorn our electronics and be found in our medical laboratories, quantum dots have had quite a journey.
Image Credit: CNN, images of the three scientists who won the Nobel Prize (Bawendi, Brus, Ekimov, in that order).
Sources
- https://www.nobelprize.org/uploads/2023/10/press-chemistryprize2023.pdf
- https://www.cnn.com/2023/10/04/europe/nobel-prize-chemistry-quantum-dots-bawendi-brus-ekimov-intl-scn/index.htm
- https://www.theguardian.com/science/2023/oct/04/nobel-prize-in-chemistry-winners-2023l
