Quantum Dots (QDs) are tiny (nanoscale) particles (some call QDs zero-dimensional materials) that feature tunable absorption spectrum and high extinction coefficients. These attractive feature make QDs very interesting for display and lighting applications - and also to solar power generation.
Quantum Dots emit photos (light) when electricity is applied (electroluminescence)- or when photons absorbed in the QD (photoluminescence ). The emitted light wavelenght is determined by the QDs size (diameter). These two properties can be used to build displays from QDs. QD-LCDs are LCD enhanced with QDs, in which blue LED light is emitted and then absorbed in a layer of QDs, that emit white light. QD-LCDs outperform regular white-LED based LCDs in terms of power efficiency and color purity.
QDs can also be used as light-emitting materials, to create OLED-like displays. This is still early technology but companies such as Samsung and others are developing QDLED displays and some estimate that commercial QDLEDs will arrive at around 2018 or 2019 to compete with OLEDs.
Beyond displays, quantum dots can be used in many types of applications, including:
The most efficient quantum dot particles are based on Cadmium. Even though a QD-enhanced LCD containts trace amount of Cadmium this is a problem as this is a heavy, toxic metal. Companies are developing Cadmium-free QDs, from all sorts of materials. One promising material for QDs is graphene.