Synthesis of platinum/reduced graphene oxide composite for cathode in dye‐sensitized solar cells

Platinum/reduced graphene oxide (Pt/rGO) composite materials with different mass ratios were fabricated by thermal decomposition method from H2PtCl6 and reduce graphene oxide (rGO) as precursors. Pt/rGO composites were used to fabricate Pt/rGO thin film cathodes by using the screen printing technology. The electrochemical properties of the fabricated cathodes were measured using the cyclic voltammetry method. Dye-sensitized solar cells (DSSCs) were assembled from fabricated cathodes and were measured the performances by current density-voltage (J-V) curves and electrochemical impedance spectroscopy (EIS). The results showed the appropriate replacement amount rGO with Pt was 40 %, with the efficiency of 4.73 %, which was higher than that of commercial Pt cathode. The characterizations of the appropriate Pt/rGO composite were investigated by Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy. X-ray diffraction (XRD) patterns indicated that the interlayer distance between the rGO was 0.35 nm while the transmission electron microscopy (TEM) image showed the Pt nanoparticles with size of 10-20 nm were evenly distributed on the rGO sheets. These results indicated that Pt/rGO could be appropriated material to replace Pt in DSSCs to reduce the produce cost and enhance the efficiency.