Gap-state engineering of visible-light-active ferroelectrics for photovoltaic applications.

ABSTRACT: Photoferroelectrics offer unique opportunities to explore light energy conversion based on their polarization-driven carrier separation and above-bandgap voltages. The problem associated with the wide bandgap of ferroelectric oxides, i.e., the vanishingly small photoresponse under visible light, has been overcome partly by bandgap tuning, but the narrowing of the bandgap is, in principle, accompanied by a substantial loss of ferroelectric polarization. In this article, we report an approach, 'gap-state' engineering, to produce photoferroelectrics, in which defect states within the bandgap act as a scaffold for photogeneration. Our first-principles calculations and single-domain thin-film experiments of BiFeO₃ demonstrate that gap states half-filled with electrons can enhance not

SUBMITTER: Matsuo H 

PROVIDER: S-EPMC5547143 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature