Disclosed herein are ferroelectric perovskites characterized as having a band gap, Egap, of less than 2.5 eV. Also disclosed are compounds comprising a solid solution of KNbO3 and BaNi1/2Nb1/2O3-delta, wherein delta is in the range of from 0 to about 1. The specification also discloses photovoltaic devices comprising one or more solar absorbing layers, wherein at least one of the solar absorbing layers comprises a semiconducting ferroelectric layer. Finally, this patent application provides solar cell, comprising: a heterojunction of n- and p-type semiconductors characterized as comprising an interface layer disposed between the n- and p-type semiconductors, the interface layer comprising a semiconducting ferroelectric absorber layer capable of enhancing light absorption and carrier separation.
STATEMENT OF GOVERNMENT SUPPORT
 The inventions disclosed herein were made using financial support from the following U.S. Federal Grants: U.S. Department of Energy (DE-FG02-07ER46431), U.S. Office of Naval Research (N00014-09-1-0157), U.S. Army Research Office (W911-NF-08-1-0067), and NSF Division of Materials Research (DMR 0907381).