Solar cells, the main device used to harness solar energy, only have on an average a 15% efficiency. One of the factors that influence solar cell efficiency is the band gap of semiconducting material. Band gap width refers to the wavelength at which a substance absorbs and emits radiation. In order to increase absorption, the band gap width of semi-conductors on a photovoltaic cell must be taken into account. Solar cells only have a certain bandgap they can absorb, correlating to a specific wavelength. Different band gap materials can lead to increased efficiency in converting solar radiation into electricity.This presents a problem: a solar cell can only absorb one wavelength of light, and with that spectrum excite only one electron per photon from the Sun. Research shows that the semiconductor material on solar cells is to blame. This has led many scientists to search for liquid forms semiconductors, because they can be conjoined to the solar cells, yet still change shapes with ease. An example of this are dyes, which can be layered on solar cells. However, this project focuses on changing the solar cell design using different semiconductors.

     Quantum dots are miniscule semi-conducting crystals that have MEG, or multiple exciton generation. This allows them to excite multiple electrons per photon of light, making them an ideal semiconductor for solar cells. Quantum dots also have a tunable bandgap, which correlates to the grain size of the crystal. This is why quantum dots come in different colors dependent on the light they absorb.

    Altering the crystal size of the quantum dots is shown to have an effect on absorption; the larger the crystal size, the more electrons that can be excited per photon of light. This project test the CuInS2 and CuInSe2 quantum dots at different crystal sizes. This is done by prolonging the time quantum dots are in heat synthesis.