Increased short-circuit current in grating-coupled surface plasmon resonance field-enhanced dye-sensitized solar cells

Abstract

In this paper, we demonstrate the fabrication of grating-coupled surface plasmon resonance (SPR)-enhanced dye-sensitized solar cells (DSSCs) and their increased short-circuit current properties. DSSCs consisted of a grating substrate/gold/TiO₂/dye/electrolyte/indium-tin oxide structure. Blu-ray disc recordables were used as diffraction grating substrates on which gold films were deposited by vacuum evaporation. TiO₂ films were prepared on the gold/grating substrates by an electrophoretic deposition technique. 5,10,15,20-Tetrakis (1-methyl-4-pyridinio) porphyrin tetra (p-toluenesulfonate) and sodium copper chlorophyllin layer-by-layer ultrathin films were deposited as the dye layer on the TiO₂ films. SPR excitation was observed in the fabricated cells upon irradiation with white light. Up to 4.5-fold increase in the short-circuit photocurrent was observed when the surface plasmon (SP) was excited on the gold gratings as compared with that without SP excitation. Finite-difference time-domain simulation indicated that the electrical field in the dye layer could be increased using the grating-coupled SP technique.