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Tobias Hanrath Current Research

Research Focus

Our research efforts focus on the fundamental study of optoelectronic properties of semiconductor nanocrystals and their application in solar energy conversion and energy storage devices.  The semiconductor nanocrystals used in our work provide a diverse set of building blocks whose electronic and optical properties differ from their bulk counterparts due to the spatial wavefunction confinement.  This quantum confinement effect allows us to engineer the materials properties through simple adjustments in nanocrystal size, shape, composition, and surface chemistry.  In addition to their immense potential for technological applications, these materials also provide a material system to experimentally test fundamental quantum mechanical concepts. 

Current Projects

Recent Advances in semiconductor nanomaterial synthesis, characterization, and the emerging understanding of their size dependent properties form a fertile area of research with many opportunities to develop next-generation energy conversion technologies. These materials unique optical and electronic properties have several potential benefits as light-harvesting materials including a large absorption cross-sections enable efficient light capture in thin films, and size tunable energy gaps present exciting opportunities for novel approaches to low-cost multigap device structures.

To harness this immense technological potential, our work seeks solutions to the following challenges. 

• How can we efficiently contact semiconductors to extract phtogenerated into an external circuit?
• Control and understand physical and chemical properties of the nanostructured interface to meet the stringent energetic, kinetic, and structural constrains to accomplish efficient separation and transfer of photogenerated charges.
• How can the kinetics of the process be probed to understand and improve the charge transfer across the boundary of the nanocrystal?
• How do we integrate the nanostructures into robust and low-cost device structures that combine the required control over interface properties and nanostructure ordering across multiple length scales?