Performance enhancement effects of dispersed graphene oxide sponge nanofillers on the liquid electrolytes of dye-sensitized solar cells

A graphene oxide sponge (GOS) is prepared and utilized as a nanofiller (NF) of an iodide liquid electrolyte for dye-sensitized solar cell (DSSC) application. The concentration effects of the GOS NFs on the conductivity of the electrolyte, and the performance of the DSSCs are studied. The results indicate that the inclusion of GOS NFs markedly enhances the conductivity of the liquid electrolyte. The electrochemical impendence spectroscopy (EIS) analysis shows that the presence of GOS NFs may increase the recombination resistance (R-ct) at the photoelectrode/electrolyte interface and, furthermore, decreases the charge transfer resistance at the Pt counter electrode/electrolyte interface (R-pt). Therefore, the current density (J(sc)), open circuit potential (V-oc), and fill factor (FF) of the DSSCs can be improved by controlling the concentration of GOS NFs. In this study, the DSSC with 0.50 wt% GOS NFs can achieve the highest energy conversion efficiency of 9.44%, which is higher than that obtained for the corresponding cell without GOS NFs (8.84%). (C) 2018 Elsevier Ltd. All rights reserved.