Sulfur-doped graphene with iron pyrite (FeS₂) as an efficient and stable electrocatalyst for the iodine reduction reaction in dye-sensitized solar cells

Abstract

As an alternative to platinum (Pt), hybrid electrocatalysts based on sulfur-doped graphene with FeS₂ microspheres (SGN-FeS₂) were used as a counter electrode (CE) in dye-sensitized solar cells (DSSCs). Benefiting from the high conductivity of SGN and excellent electrocatalytic activity of the FeS₂, the bifunctional hybrid electrocatalyst-based device displays a power conversion efficiency (PCE) of 8.1%, which is comparable to that (8.3%) of traditional Pt CE-based DSSC, while also exhibiting excellent stability in ambient conditions. These characteristics, in addition to its low-cost and facile preparation, make the SGN–FeS₂ hybrid an ideal CE material for DSSCs.