Materials for downconversion in solar cells: Perspectives and challenges

Solar energy has an enormous potential to solve society energy needs in a sustainable way. Notably, photovoltaic systems (PV) permit to obtain electricity based on solar energy. However, some issues must be addressed to establish PV as a reliable source of electrical power, for example, its low energy density. One of the approaches to improve the performance of PV systems is to utilize the solar spectrum in solar cells efficiently. Downconversion (DC) is a process where a high energy photon is converted into two or more photons with lower energy. Trough downconversion is possible to use a wider portion of the solar spectrum raising the efficiency in different kinds of solar cells. The present paper reviews the state of the art of materials and methods used to take advantage of downconversion processes in solar cells. Here we discuss some of the pros and cons of different designs in solar cells as well as the main characteristics of the materials utilized.