静电喷雾法制备高效染料敏化太阳能电池的二氧化钛光阳极
摘要
In dye-sensitized solar cells (DSSC), one of the key components is TiO<sub>2</sub> anode, which plays an important role in determining the device efficiency. TiO<sub>2</sub> electrodes are generally prepared by doctor blade or screen printing. Electrostatic spray (ES) has started to get attention for TiO<sub>2</sub> electrodes preparation in recent years. The preparation of photoanode by electrostatic spray depends on many factors, such as voltage, feeding rate, concentration of the TiO<sub>2</sub> suspension, spray distance and time, etc. However, the influences of these factors on the fabrication and the device performance have not been reported. This work describes the detail of TiO<sub>2</sub> anodes preparation by ES method and their corresponding DSSC devices characterization. TiO<sub>2</sub> powders (i.e. P<sub>25</sub> powder) was dissolved in ethanol and dispersed thoroughly under suitable ultrasonic process, yielding TiO<sub>2</sub> suspension with high stability and quality. This well dispersed TiO<sub>2</sub> suspension was sprayed onto the FTO under a high electronic field. TiO<sub>2</sub> photoanodes with different microstructures and morphologies were obtained by changing the spraying distance; their formation mechanism and impact on the cell performance were studied. Moreover, it was also showed that the post-treatment with TiCl<sub>4</sub> aqueous could significantly improve the efficiency of the cell. By optimizing, high power conversion efficiency of 6.24% could be achieved under the following condition: liquid feeding rate of 0.8 mL/h, spraying distance of 2.2 cm, spraying time of 8 min.