Improvement of Photoinduced Properties of Narrow Bandgap Ferroelectric Thin Film Utilizing Localized Surface Plasmon Resonance of Silver Nanoparticles

Abstract

Recently, ferroelectrics with relatively small bandgap energy have been receiving much attention because of the characteristic photoinduced electrical responses under visible light irradiation. However, such photoresponsive materials have serious problems such as poor photoelectric conversion properties, especially low photocurrent. It revealed that incorporation of silver (Ag) nanoparticles in the film as a surface plasmon excitation agent is effective to enhance photocurrent of narrow bandgap ferroelectric (such as BiFeO₃) thin films. The synthesized BiFeO₃ and Ag nanoparticle/BiFeO₃ thin films demonstrated rapid on/off responses of photocurrent to visible light. The Ag nanoparticle-embedded BiFeO₃ film exhibited a several times higher photocurrent than the BiFeO₃ film.