Development of polypyrrole/graphene (PPY/graphene) based electrocatalyst for platinum free dye-sensitized solar cells (DSSCs)

•PPY/Graphene Nanocomposites were prepared by in-situ polymerization method.•Nanocomposites were employed as electrocatalysts for the applications of DSSCs.•SEM analysis of PPY/GR shows the well adhesion between the constituents of nanocomposites.•The concentration of graphene in composites effect the performance of DSSCs. The purpose of this study was to fabricatePlatinum-free counter electrode (CE) materials for energy conversion devices. Initially, pyrrole was polymerized overnight in deionized water followed by 72 h of drying at 60 °C to obtain powdered PPY. Similarly, in-situ polymerization of pyrrole yielded PPY/graphene nanocomposite with variable graphene concentrations (2–8 wt%). Powdered samples were characterizedby SEM, XRD, and FTIR for compositional and morphological analysis. CEs of dye-sensitized solar cells (DSSCs) were made with PPY and PPY/graphene composites. The dye-sensitized TiO2 photoanodes were connected to CEs to carry out current–voltage measurements usingKeithley Solar Simulator. The DSSCs with PPY/4 %graphene CE showedthe highest efficiency (3.06%).