Showing papers by "Brian C. O’Regan published in 2005"
TL;DR: Solid-state dye-sensitized solar cells of the type TiO(2)/dye/CuSCN have been made with thin Al(2)O(3) barriers between the TiO (2) and the dye, showing improved voltages and fill factors but lower short-circuit currents.
Abstract: Solid-state dye-sensitized solar cells of the type TiO2/dye/CuSCN have been made with thin Al2O3 barriers between the TiO2 and the dye. The Al2O3-treated cells show improved voltages and fill factors but lower short-circuit currents. Transient photovoltage and photocurrent measurements have been used to find the pseudo-first-order recombination rate constant (kpfo) and capacitance as a function of potential. Results show that kpfo is dependent on Voc with the same form as in TiO2/dye/electrolyte cells. The added Al2O3 layer acts as a “tunnel barrier”, reducing the kpfo and thus increasing Voc. The decrease in kpfo also results in an increased fill factor. Capacitance vs voltage plots show the same curvature (∼150 mV/decade) as found in TiO2/dye/electrolyte cells. The application of one Al2O3 layer does not cause a significant shift in the shape or position of the capacitance curve, indicating that changes in band offset play a lesser role in the observed Voc increase. Cells made with P25 TiO2 have, on ave...
326 citations