Low Cost Fabrication of Graphene Oxide Films As Efficient Counter Electrode for Dye-Sensitized Solar Cells (DSSC)

Abstract

Graphene-oxide was prepared by screen printing to validate as an alternative counter electrode material to platinum in dye sensitized solar cells. The synthesis of graphene oxide was carried out by modified Hummer’s method using graphite flakes. Subsequently, graphene oxide paste was prepared by mixing α-terpineol and ethyl cellulose, which was screen-printed on FTO glass (TEC8) substrates. The screen printed films were subjected to annealing at 450°C for 30 minutes. The graphene oxide films were characterised by X-Ray Diffraction, Scanning Electron Microscopy and Raman spectroscopy for the required identification. The device fabrication was carried out by coupling TiO2 films soaked in N719 dye with Surlyn as the spacer between the electrodes. The J-V measurements were carried out with the help of the solar Simulator AM1.5G condition under standard one Sun illumination. The DSSC fabricated with graphene oxide as counter electrode exhibited photoconversion efficiency of 5.58% whereas, platinum based devices showed photoconversion efficiency of 7.57%. The catalytic properties of graphene oxide films are being investigated by cyclic voltammetry and electrochemical Impedance spectroscopy. The present study suggests that graphene oxide counter electrodes can be considered as a promising alternative to platinum, with further optimisation, which clearly has advantages in terms of its abundance and low cost processing towards industrial prospects.