Evaluation of the efficiency potential of intermediate band solar cells based on thin-film chalcopyrite materials

Abstract

This paper discusses the potential of the intermediate band solar cell (IBSC) concept to improve the efficiency of thin-film chalcopyrite solar cells. The results show that solar cells based on CuGa S2, with a radiative limiting efficiency of 46.7%, exhibit the highest potential. A simple method for the identification of transition elements that when incorporated in CuGa S2 could possibly introduce an intermediate band is also described. The IBSC concept is also applied under the assumptions that thin-film solar cells are not to be operated under concentrated light and that a non-negligible contribution of nonradiative recombination exists. © 2008 American Institute of Physics.