Nanosociety Meeting Friday @ 12:00 pm, McCullough 115: Pore Filling & Light Trapping in Solid State Dye-sensitized Solar Cells

Friday at 12 pm, I-Kang Ding, a member of the McGehee group, will be presenting research on solid state dye-sensitized solar cells in McCullough 115.

As always, the meeting will be in McCullough 115, and FREE PIZZA will be served at 11:55 am.

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Pore Filling & Light Trapping in Solid State Dye-sensitized Solar Cells

I-Kang Ding
Department of Materials Science and Engineering
McGehee Group

Dye-sensitized solar cells (DSCs) are among the promising PV technologies that could potentially replace the expensive silicon. Liquid electrolyte-based DSCs have the highest efficiency but they suffer from potential stability and encapsulation problems. People are actively pursuing the solid state dye-sensitized solar cells (ss-DSCs), which uses a solid-state hole-transport material to replace the liquid electrolyte. SS-DSCs can potentially achieve higher power conversion efficiencies than the liquid-electrolyte because the open-circuit voltage can be adjusted by the choice of different hole-transport materials. However, current ss-DSCs are limited by both pore filling and electron-hole recombination such that the optimal thickness is around 2 micron, far thinner than the thickness needed to achieve good optical absorption.

Here we describe two approaches to improve the efficiency of the solar cell. The first one is to increase pore filling of hole transport material. Pore filling has important consequences in the efficiency of the device because increasing pore filling could lower the recombination loss by allowing holes to stay away from the electrons in TiO2, which in turn may increase the optimum thickness of the device. The second approach is to increase the absorption of the device through the use of plasmonic back reflectors, which consist of two-dimensional (2D) array of silver nanodomes. They are incorporated into the ss-DSCs by nanoimprint lithography, and they enhance absorption through excitation of plasmonic modes and increased light scattering.