High performance platinum-free counter electrode of molybdenum sulfide–carbon used in dye-sensitized solar cells

A high porous molybdenum sulfide–carbon (MoS2–C) hybrid film was prepared by using an in situ hydrothermal route. The MoS2–C hybrid film served as a low-cost and high efficient platinum-free counter electrode for a dye-sensitized solar cell (DSSC). The cyclic voltammetry, electrochemical impedance spectroscopy and Tafel curve analysis indicate that the MoS2–C electrode possesses low charge transfer resistance on the electrolyte–electrode interface, high electrocatalytic activity and fast reaction kinetics for the reduction of triiodide to iodide at the counter electrode, which is due to large specific surface area and special structure and compositions of MoS2–C film. A DSSC with the novel MoS2–C counter electrode achieve a high power conversion efficiency of 7.69% under standard light illumination, which exceeds that of the DSSC with a Pt counter electrode (6.74%).