Counter electrodes from polyaniline−graphene complex/graphene oxide multilayers for dye−sensitized solar cells

• PANi-graphene complexes are synthesized by a reflux method for rapid charge-transfer.
• (PANi-G/GO)n multilayer CEs are fabricated by a self-assembly technique.
• The charge-transfer ability toward iodide reduction is significantly enhanced.
• A power conversion efficiency of 7.88% is measured in an optimal DSSC.
• The strategy provides new opportunities for efficient DSSC assembly.

In order to enhance the charge-transfer ability, positively charged polyaniline-graphene complexes are synthesized by a reflux method and assembled into multilayers with negatively charged graphene oxide. The counter electrodes from polyaniline-graphene/graphene oxide (PANi-G/GO)n (n represents the bilayer number) multilayers show superior electrocatalytic activity and electrical conductivity because of enormous interface. An impressive power conversion efficiency of 7.88% is recorded from the DSSC employing PANi-G/GO multilayer counter electrode. The multilayer counter electrodes and the resultant DSSCs are thoroughly assessed by electrochemical characterizations. The results are far from optimal but the preliminary photovoltaic performances make the strategy promising in efficient DSSC applications.