Investigation on the Performance of Reduced Graphene Oxide as Counter Electrode in Dye Sensitized Solar Cell Applications

In dye sensitized solar cells (DSSC), the counter electrode (CE) plays a significant role in electro catalytic reaction in redox region to achieve maximum power conversion efficiency (PCE) of the DSSC. The graphene oxide (GO) is synthesized by Hummer's method and converted to reduced graphene oxide (RGO) by thermal method. The effect of binders such as NMP, PVP, and nafion for RGO are investigated. The field emission scanning electron microscope (FESEM) of RGO shows the fine layers like structure. The surface area of the RGO is found to be 110.16 m2 g−1 by Brunauer–Emmett–Teller (BET) method and pore volume 0.5182 cm3 g−1 of RGO by Barrett–Joyner–Halenda (BJH) method. The Raman spectra is used to analyze the structural defects and changes of GO and RGO. The crystallite size of GO is 18.6 nm, and RGO is 20.9 nm calculated from the Raman spectrum. For analyzing the electro catalytic properties of the RGO/NMP/PVP, RGO/NMP, and RGO/nafion based CE materials cyclic voltammetry is performed and its maximum current density was measured. The composition of RGO/NMP/PVP based CE exhibits better electro‐catalytic properties when compared to other RGO/NMP and RGO/nafion based counter electrodes. Maximum PCE exhibited by RGO/NMP/PVP CE based DSSC is 5.8%. In this study the electrocatalytic behaviors of reduced graphene oxide (RGO) with different binder combinations is investigated. The binder's role is studied with the optical microscope. RGO with binders polyvinylpyrrolidone (PVP), N‐methyl pyrrolidone (NMP), and nafion based CE thin films exhibit power conversion efficiency of 5.8, 4.5, and 3.4%, respectively.