TiO2-poly(3,4-ethylenedioxythiophene) composite counter electrode to improve the performance of CdS quantum-dot-sensitized solar cell with polysulfide electrolyte

TiO2-poly(3,4-ethylenedioxythiophene) composite counter electrode(CE) has been prepared by electropolymerization of poly (3,4-ethylenedioxythiophene) (PEDOT) in the TiO2 film and its performance in CdS quantum-dot-sensitized solar cell (QDSSC) is studied. The QDSSC with TiO2-PEDOT CE achieves a power conversion efficiency of 1.56%, enhances 20% compared with that of the cell with pure PEDOT CE mainly due to the superior electrocatalytic activity by the increasing active surface area. Electrochemical impedance spectra (EIS) reveals that the TiO2-PEDOT CE exhibits reduced charge transfer resistance at the electrolyte/CE interface compared with the pure PEDOT CE. Furthermore, the influences of the electrolyte and the charge passed for TiO2-PEDOT on the performance of QDSSC are also investigated.