Flexographic printing of grapheme nanoplatelet ink to replace platinum as counter electrode catalyst in flexible dye sensitised solar cell

A semitransparent catalytically active graphene nanoplatelet (GNP) ink was developed suitable for roll to roll printing onto a flexible indium tin oxide substrate at a speed of 0·4 m s−1. Dye sensitised solar cells using this ink as a catalyst demonstrated efficiencies of 2·0%, compared with 2·6% for sputtered platinum. Given further optimisation, GNP inks have the potential to replace chemically reduced or sputtered platinum. This would have the benefit of replacing the chemical reduction or sputtering operations as well as providing potential material cost benefits.