Better solar cells with the help of quantum dots
Prof. Erik Johansson and his research group, at the Department of Chemistry at the Ångström Laboratory, focuses on solar cells. With the help of quantum dots, they have showed that you can make a kind of super light, flexible and environmentally friendly solar cells.
Quantum dots are particles so small that their optical and electronic properties change compared to a larger piece of the same material. This phenomenon was discovered and has been studied by this year's Nobel laureates in chemistry; Lous E. Brus, Alexei I. Ekimov and Moungi G. Bawendi. The reason for the changed properties can be explained with quantum physics, and the limited space of the electrons in the nanometer-sized particles, which has given rise to the name quantum dots. Lous E. Brus and Alexei I. Ekimov discovered that small enough particles of material can produce a change in color and light absorption and Moungi G. Bawendi has developed chemical synthesis methods to make quantum dots.
Quantum dots are already used today, for example in new TV's due to their ability to efficiently emit light, and the ability to determine the color of the emitted light with the size of the nanoparticle. At Uppsala University, Prof. Erik Johansson's research group is researching the possibility of using quantum dots in solar cells, in order to achieve a high efficiency for converting sunlight into electricity.