(98e) Light Harvesting in Dye Sensitized Solar Cell Based on Consensitizer in Core-Shell Nanofiber Configuration Reducing Charge Recombination

Dye sensitized solar cell offers the potential of being a low-cost, high-efficiency photovoltaic device. However, the power conversion efficiency is limited as it cannot utilize all photons of the visible solar spectrum. A novel design of a core-shell photoanode is presented herein where a thin-shell of infrared dye is deposited on the core of sensitized TiO₂ nanofiber. Specifically, the ruthenium based dye (N719) sensitized TiO₂ nanofiber is wrapped by a thin-shell of copper phthalocyanine (CuPc). In addition to broadening the absorption spectrum, this core-shell configuration further suppresses the electron-hole recombination process. Instead of adopting the typical Förster resonance energy transfer, upon photons being absorbed by the infrared dye, electrons are transferred efficiently through a cascade process from the CuPc to the N719 dyes, the conduction band of TiO₂, the FTO electrode and finally the external circuit. This results in a high power conversion efficiency of 9.48% for the device. The proposed strategy provides an alternative method for enhancing the performance of DSSC for low-cost renewable energy in the future.