Effect of perovskite-PbTiO3 as a buffer or scattering layer in DSSC performance

To enhance the current efficiency of dye-sensitized solar cells, a perovskite-PbTiO3 as a buffer or scattering supplement is introduced via a conventional hydrothermal treatment in this study. For comparison, five groups of multi-layered electrodes with different configurations are fabricated, TiO2/TiO2 (blocking layer/scattering layer), TiO2/PbTiO3 and TiO2/TiO2-PbTiO3/PbTiO3 (blocking layer/buffer layer/scattering layer), and the photoelectrochemical properties of these materials are identified by Xray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, impedance measurements (EIS), intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS) analysis. When a mixture of TiO2 and PbTiO3 is prepared as a buffer layer, the cell efficiency is improved remarkably. In particular, TiO(2)b/5TiO(2)b-5PbTiO(3)/PbTiO3-DSSC shows the highest cell performance of 8.39% with the smallest internal resistance This result means that the improved electron recombination and transportation over the TiO(2)b/5TiO(2)b-5PbTiO(3)/PbTiO3-DSSC lead to higher efficiency. Based on the photoelectrochemical results, the perovskite-PbTiO3 can be concluded to be a valuable material to reduce the presence of defects at the interface and facilitate the movement of electrons for higher DSSC performance. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.