Phosphonium iodide as a donor liquid electrolyte for dye-sensitized solar cells

An efficient triphenylmethylphosphonium iodide-based liquid electrolyte was synthesized and used for the first time as an electrolyte in dye-sensitized solar cells (DSSCs). With the as-synthesized electrolyte, the DSSC yielded an overall light to electricity conversion efficiency of 5.34 to 7.10 %, when the radiant power was tuned from 100 to 10 mW cm super(-2). This may be attributed to the limitation of mass transport in the DSSC. The electronic and ionic processes in the DSSC were investigated by electrochemical impedance spectroscopy and linear voltammography, respectively.