Polyaniline nanotube/reduced graphene oxide aerogel as efficient counter electrode for quasi solid state dye sensitized solar cell

Polyaniline nanotube/reduced graphene oxide aerogel (PAniNT/rGOA) is studied as a potential counter electrode material for a quasi-solid-state dye-sensitized solar cell (DSSC) fabricated with poly(methyl methacrylate) based polymer gel electrolyte. The aerogel, prepared via an organic sol-gel route, having a high surface area of 294.73 m(2) g(-1) exhibits excellent electro-catalytic activity towards the reduction of triiodide ions in the electrolyte. The excellent catalytic activity of the aerogel based electrodes is manifested with cyclic voltammetry based analyses. Electrochemical impedance analyses and current density vs voltage plots are employed to gauze the photovoltaic performance of the DSSCs fabricated with PAniNT/rGOA counter electrode. The thickness of the counter electrode is a crucial factor that affects the performance of the DSSC: thicker films offer more surface area for electro-catalytic reduction reaction whilst increasing the charge and mass transport resistances simultaneously. At an optimum PAniNT/rGOA electrode film thickness of 8.68 mu m, a power conversion efficiency of 5.47% is achieved. In addition, an improvement of open circuit voltage is observed due to the capacitance involved at the electrolyte/electrode interface.