Advanced concepts of photovoltaics based on III-V compounds

With 25.6% conversion efficiency, solar cells based on the c-Si generation reach their limits. However, the third generation solar cells, such as multijunction solar cells and hot-carrier solar cells (HCSCs), allow to overcome the intrinsic limit of a single junction. Firstly, we show the first stage developments of a GaAsPN/Si tandem cell on Si, which benefit from the low cost and technological maturity of Si cells. The GaAsPN dilute-nitride compound, grown by MBE, is quasi lattice-matched with Si, and displays the required the required 1.7 eV pseudo-bandgap. Secondly, HCSCs aim to reduce the thermalization process which is a major loss in a classical PV cells. This can be done by the reduction of the electron-phonons interactions in quantum wells (QWs) structures. Therefore, we have investigated a InGaAsP multi-QWs heterostructure epitaxially grown on a InP(001) substrate and demonstrate its potential to work as a hot carrier cell absorber. Finally, some outstanding properties of the hybrid organic perovskites, a very new technology which has quickly reached conversion efficiency larger than 20%, will be presented, along with results from a collaboration between FOTON laboratory, Los Alamos National Laboratory, Rutgers University New Jersey, Purdue university, Brookhaven National Laboratory and Chemical Sciences Institute of Rennes.