|Ultrasmall CdSe Quantum Dots as Photoactive Materials for Light Harvesting Devices|
|Megan M. Webster, Marco J. Castaldi, Ilona Kretzschmar
City College of New York, New York, NY, United States
When excited by UV light, ultrasmall (sub-2 nm) CdSe QDs exhibit broad emission over the entire visible spectrum despite sample monodispersity. Investigation of their band structure was conducted via UV-vis, PL, and UPS spectroscopy. Ligated and unmodified QDs were incorporated into mesoporous TiO2 networks and their performance as solar cell sensitizers was compared to N719 dye. Performing on par with N719 under white light conditions, the unmodified QD cells have greater JSC and VOC than N719 cells in UV lighting conditions, demonstrating superiority at collecting energy from higher light frequencies. Thiolated QDs suffered compared to unmodified, likely due to the insulating nature of alkanethiol ligands.
Area: Sub-Area 1.2: Quantum-well, Wire, and Dot-Architectured Devices