An evaluation of BiFeO3 as a photovoltaic material

An analysis of BiFeO3, focusing on its absorption properties, is carried out using experimental results from the literature and first-principles. In order to identify the different contributions to the absorption coefficient, the results have been split into inter- and intra-atomic contributions. Its potential as a photovoltaic material has been evaluated using both theoretical and experimental optical results. Because of the ferroelectric properties, we have considered two mechanisms for generating photocurrent: the traditional radiative and the ferroelectric or photovoltaic effects. The efficiencies, when ferroelectric photogeneration coexists with the traditional photovoltaic mechanism, are only slightly larger than when only the latter is considered. However, the increase in efficiency is significant with just multi-gap solar cells.