Scalable low-cost SnS(2) nanosheets as counter electrode building blocks for dye-sensitized solar cells.

A new type of semitransparent SnS2 nanosheet (NS) films were synthesized using a simple and environmentally friendly solution-processed approach, which were subsequently used as a counter electrode (CE) alternative to the noble metal Pt for triiodide reduction in dye-sensitized solar cells (DSSCs). The resultant SnS2 -based CE with a thickness of about 300 nm exhibited excellent electrochemical catalytic activity for catalyzing the reduction of triiodide and demonstrated comparable power conversion efficiency of 7.64 % with that of expensive Pt-based CE in DSSCs (7.71 %). When functionalized with a small amount of carbon nanoparticles, the SnS2 NS-based CE showed even better performance of 8.06 % than Pt under the same conditions. Considering the facile fabrication method, optical transparency, low cost, and remarkable catalytic property, this study on SnS2 NSs may shed light on the large-scale production of electrocatalytic electrode materials for low-cost photovoltaic devices.