Single Walled Carbon Nanohorns as Catalytic Counter Electrodes for Co(III)/(II) Electron Mediators in Dye Sensitized Cells

The electrochemical properties of both pristine single walled carbon nanohorns (SWCNHS) and their chemically oxidized form (ox-SWCNHS) spray coated onto fluorine doped SnO2 (FTO) were investigated in the framework of the fabrication of cobalt based transparent dye sensitized solar cells (DSSCs). These new nanocarbon substrates, evaluated in conjunction with the Co(bpy)3 2+/3+ (bpy = 2,2′-bipyridine) redox mediator, are endowed with excellent electrocatalytic properties, ease of fabrication, and very promising stability and display a great potential for replacing the best noble metal and conductive polymer catalytic materials in the building of semitransparent counter electrodes in new generation photoelectrochemical devices.