Quantum dots

The Nobel Prize in Chemistry for 2023 celebrates the re­markable discovery and advance­ment of quantum dots (QDs). To comprehend their significance, let’s begin with a fundamental concept: the characteristics of an element depend on the number of electrons it holds. However, when we scale matter down to the na­noscale, something extraordinary unfolds—we enter the realm of quantum phenomena.

QDs—these incredibly minute nanomaterials, typically measur­ing between 2 and 8 nanometers—stand at the heart of this scientific breakthrough. Due to their excep­tionally small size, electrons with­in QDs find their movements re­stricted in all directions. What’s truly remarkable is that this size-dependent behaviour grants sci­entists the power to precisely ma­nipulate the properties of these QDs. This remarkable ability to fine-tune their characteristics eliminates the need for expensive semiconductor materials.

In the early 1980s, Alexei Eki­mov achieved a breakthrough by creating size-dependent quantum effects in coloured glass. The co­lours originated from nanoparti­cles of copper chloride, and Eki­mov demonstrated that particle size influenced the glass’s colour through quantum effects. A few years later, Louis Brus became the world’s first scientist to prove size-dependent quantum effects in particles suspended freely in a flu­id. In 1993, Moungi Bawendi rev­olutionised the chemical produc­tion of QDs, resulting in nearly perfect particles. This high-quali­ty production was crucial for their utilisation in various applications.

These wondrous QDs have found their way into a myriad of incred­ible applications in the field of nanotechnology. They work their enchantment to enhance the bril­liance of your television and LED lamps, making your viewing ex­perience more vibrant. Howev­er, their magic doesn’t stop there; these mystical QDs serve as guid­ing lights for surgeons during complex procedures, particular­ly when navigating intricate chal­lenges like tumour removals. They assist doctors in pinpointing pre­cisely where to make their inci­sions, enhancing the safety and precision of surgeries.

Today, QDs are making substan­tial contributions to benefit hu­mankind. Researchers believe that in the future, they could play pivot­al roles in shaping flexible electron­ics, miniature sensors, thinner and more efficient solar cells, and en­crypted quantum communication. The potential of these minuscule particles is just beginning to unfold.

DR INTIKHAB ULFAT

KARACHI