(375b) Dye-Anchored Nanocatalysts for Improved Solar Energy Conversion Efficiency in Dye-Sensitized Solar Cells

With the demand for sustainable and renewable energy, solar cell devices have attracted much attention which can directly convert solar energy into electrical power with the least environmental impact. Dye sensitized solar cells (DSSCs) are a very promising technology due to their attractiveness as cost-effective alternatives to conventional silicon-based photovoltaic devices. In the DSSCs, the dye is left oxidized after photo injecting an electron. A redox couple usually comprised of I^–/I₃^– in the electrolyte regenerates the oxidized dye to its neutral state and carrys the positive charge to the platinized counter-electrode. I^–/I₃^– has been commonly used as the redox couple due to the high ion mobility and slow recombination of electrons from TiO₂ to the oxidized species, triiodide (I₃^–). However, the regeneration of oxidized dye by I^– is not a simple one step reaction, which causes a large voltage loss of about 0.5–0.6 V due to the formation of diiodide radicals (I₂^–•).

The talk will be focusing on reducing the overpotential of dye regeneration in DSSCs, including the preparation of Pt nanocatalyst, synthesis of new dye molecule, binding the dye to Pt nanoparticles and the assembling of TiO₂–dye–Pt system. In the earlier study, Pt nanoparticles have been prepared as the localized catalyst for the dye regeneration. A new dye molecule is synthesized with dithiolane groups for the binding to Pt nanoparticles. The aim of this talk is to demonstrate the proof-of-concept of using Pt nanoparticles to catalyze the regeneration of dye by I^– to reduce the overpotential hence improve the performance of DSSCs.