Molten and Solid Trialkylsulfonium Iodides and Their Polyiodides as Electrolytes in Dye-Sensitized Nanocrystalline Solar Cells

Abstract

Potential new electrolytes for dye-sensitized nanocrystalline solar cells (DNSCs) of Grätzel type based on trialkylsulfonium iodides have been investigated. Room temperature molten salts of (Et 2 MeS)I, (Bu 2 MeS)I, and (Bu 2 EtS)I, with iodine in low concentrations, revealed good conducting abilities. DNSCs using iodine-doped (Bu 2 MeS)I as electrolyte achieved an overall light-to-electricity conversion efficiency of 3.7% in simulated AM 1.5 solar light at a light intensity of 0.1 Sun. The effects from varying the temperature during the I/V measurements were studied, as well as the effects of 4- tert -butylpyridine treatment of the electrodes.