Two-Dye-Molecule-Stacked Structures on ZnO Films Formed by Liquid-Phase Molecular Layer Deposition (MLD) for Waveguide-Type Photo-Voltaic Devices

Abstract

We propose a waveguide-type two-dye-sensitized photo-voltaic device with flat thin film semiconductors. P-type dye molecule (rose bengal (RB)) and n-type dye molecule (crystal violet (CV)) were successively deposited on n-type ZnO thin films by the liquid-phase molecular layer deposition (MLD) to form a n/p/n structure of ZnO/p-type dye/n-type dye. The photocurrent spectra were widened in the n/p/n structure, where, electrons excited in the n-type dye molecules and the p-type dye molecules are injected into ZnO with large efficiency. The guided light configuration achieved sufficient light absorption in the dye molecules to enhance the photocurrents by about one-order of magnitude.