Enhanced Photocurrent-Voltage Characteristics of Ru(II)-Dye Sensitized TiO[sub 2] Solar Cells with TiO[sub 2]-WO[sub 3] Buffer Layers Prepared by a Sol-Gel Method

The influence of a buffer layer of a composite material located between a TCO substrate and a (P25) layer on photocurrent-voltage characteristics of dye-sensitized solar cells was compared. The buffer layer effectively isolated dye molecules and electrolytes from directly contacting the conducting substrate. In the presence of the buffer layer having 15-75 mol % both open-circuit photovoltage and short-circuit photocurrent were enhanced. Analyses of scanning electron microscopy data and bandedge positions of the films indicate that the and increases are correlated with favorable energy levels for the electron injection from the P25 layer, and with improved interparticle electrical contacts at both the and the junctions.