Photocurrent enhancement of perovskite heterojunction by plasmonic nanoparticles and ferroelectric polarization

Perovskite oxides—Pb0.86La0.14TiO3 (PLT), AgNbO3 (ANO), and SrTiO3 (STO)—were deposited consecutively on ITO/glass substrates to form layered composite photoelectrodes. These materials were chosen for their specific electronic band structures to form efficient photocatalytic heterojunctions and similar crystalline structures to minimize interface defects. Two additional methods were adopted to increase the photocurrent density of the composites: (1) plasmonic gold nanoparticles were introduced at the PLT/ITO interface to enhance light scattering and absorption while not becoming electron trapping centers and (2) the ferroelectric PLT layer was electrically poled toward the ANO layer to create a favorable band bending for electron transfer.