Tailoring the photocurrent in BaTiO3/Nb:SrTiO3 photoanodes by controlled ferroelectric polarization

We demonstrate on prototypical samples containing a ferroelectric layer (BaTiO3/Nb:SrTiO3) that the efficiency of the system, used as photoanode, substantially depends on the polarization state of the ferroelectric layer. We show a significant increase of the photocurrent by a factor larger than 2 when the BaTiO3 film is downward polarized. We explain this finding by the presence of an internal electric field which favors the separation of photo-generated charges. (C) 2015 AIP Publishing LLC.