Michio Suzuka

A Quasi-Solid State DSSC with 10.1% Efficiency through Molecular Design of the Charge-Separation and -Transport

Organic-based solar cells potentially offer a photovoltaic module with low production costs and low hazard risk of the components. We report organic dye-sensitized solar cells, fabricated with molecular designed indoline dyes in conjunction with highly reactive but robust nitroxide radical molecules as redox mediator in a quasi-solid gel form of the electrolyte. The cells achieve conversion efficiencies of 10.1% at 1 sun, and maintain the output performance even under interior lighting. The indoline dyes, customized by introducing long alkyl chains, specifically interact with the radical mediator to suppress a charge-recombination process at the dye interface. The radical mediator also facilitates the charge-transport with remarkably high electron self-exchange rate even in the quasi-solid state electrolyte to lead to a high fill factor.

Dye-sensitized Solar Cells Using Scattering Layer with Micron-sized Pores for Indoor Light Energy Harvesting

Dye-sensitized solar cells (DSSCs) using scattering layer with micron-sized pores were prepared by a polymer template method. The scattering layer displayed low reflectance over a range of wavelengths (600 nm to 700 nm) compared with scattering layer composed of submicron TiO2 particles. The energy conversion efficiency of these DSSCs reached 21 % under indoor light conditions (57.7 μW/cm).