Solvent effect in photo-ionic cells

Photo-ionic cells convert solar energy into redox fuels. Unlike in photovoltaic devices where the photo-induced charge transfer reactions occur at an electrode, the photoreaction takes place in one bulk solution of a biphasic liquid-liquid system, and the charge separation is realised by the transfer of one of the photoproducts into the adjacent phase to avoid recombination. After separation of the two phases, the redox fuels can be stored and then converted to electricity on demand with a biphasic fuel cell. Here, we compared the effect of the two organic solvents, 1,2-dichloroethane and propylene carbonate, on the performance of the photo-ionic cell. By replacing 1,2-dichloroethane, the maximum cell voltage was increased to 0.6 V. Additionally, propylene carbonate helps to reduce aggregation of dyes and it shows faster kinetics for the photoreaction.