A Controllable Method for Electrochemical Deposition Formed Crystalline MoS₂ As a Counter Electrode for Dye-Sensitized Solar Cells

In this study, the two-dimensional nanomaterials of molybdenum disulfide (MoS2) were synthesized onto the fluorine-doped tin oxide (FTO) glass substrate via the electrochemical deposition (ECD) method. By controlling the potential during the ECD processes, the MoS2 thin films were deposited homogenously onto a large area of FTO glass. It was observed that the edge planes of MoS2 provided plenty active sites for an efficient counter electrode (CE) of the dye-sensitized solar cells (DSSCs). The electrochemical properties of the controllable the MoS2 thin films were characterized and compared with the Platinum (Pt) films prepared by the e-gun technology. The electrochemical activity of the MoS2 CE was performed by cyclic voltammetry (CV), electrochemical impedance spectroscope (EIS) and also assembled as the Pt-free DSSCs. In combination with a dye-sensitized TiO2 working electrode and an iodine-based electrolyte, the DSSC with the MoS2 CE showed a photovoltaic conversion efficiency of 6.089 % under the illumination of AM 1.5 (100 mWcm-2). The results demonstrated that the ECD method displayed a facile and economical process to synthesize the low-cost MoS2 CE for the cost-effective DSSCs.