Boron doped ZnO films for dye-sensitized solar cell (DSSC): effect of annealing temperature

Abstract

The paper reports the influence of annealing temperature on the properties of B-doped ZnO films. These films properties were then correlated to the performance parameters of dye-sensitized solar cell (DSSC) utilizing those films. The B-doped ZnO samples were grown on FTO glass substrate via seed mediated hydrothermal method and then annealed at various temperatures, namely, 150, 250, 350 and 450 °C. It was found the morphological shape of the sample is the mixture of nanotube and nanorod. The diameter of the nanotube decreases with annealing temperature. However, the length of the nanotube decreases with the temperature. The weight and atomic percentage of boron also decrease with the temperature. All samples exhibit wurtzite phase structure. The sample annealed at 250 °C shows the highest optical absorption in visible region and the lowest photoluminescence in infrared region. The DSSC utilizing the sample annealed at 250 °C demonstrates the highest photovoltaic parameters with the JSC of 2.2 mA cm−2, VOC of 0.46 V and η of 0.29 % since it shows the highest absorption in visible region, lowest photoluminescence in infra-red region and lowest Rct.