Efficient sensitization of mesoporous TiO2 film with CdSe nanospherical particles for application in dye-sensitized solar cell

摘要

Dye-sensitized solar cells were successfully fabricated from sensitized mesoporous TiO2 films which consist of CdSe nanospherical particles. Sensitization was carried out by successive ionic layer adsorption and reaction (SILAR) process through five cycles. Scanning electron microscope (SEM) images confirmed the formation of CdSe individual nanospherical particles on the surface of mesoporous TiO2 films. With the enhancement of SILAR cycles, the number of CdSe nanospherical particles were increased so much that after five cycles, they joined and formed a porous cover on the surface of mesoporous TiO2 film. The absorbance spectra measured by UV-Vis spectrophotometer revealed that with the enhancement of SILAR cycles, the absorption of the films increased and the absorption edges shifted to the longer wavelengths. Photovoltaic measurements clarified that the short circuit current and the open circuit voltage were increased with the enhancement of SI LAR cycles and reached to 6.59 mA/cm2 and 0.742 V after five SILAR cycles, respectively. As a result, the maximum power conversion efficiency of 2.93 % was obtained after sensitization of five SILAR cycles.