Global and local aspects of the surface potential landscape for energy level alignment at organic-ZnO interfaces
Hybrid systems of organic and inorganic semiconductors are a promising route for the development of novel opto-electronic and light-harvesting devices. A key ingredient for achieving a superior functionality by means of a hybrid system is the right relative position of energy levels at the interfaces of the two material classes. In this Perspective, we address the sensitivity of the potential energy landscape at various ZnO surfaces, a key ingredient for interfacial energy level alignment, by combining one- and two-photon photoelectron spectroscopy with density-functional theory calculations (DFT). We show that even very large work function changes (>2.5 eV) do not necessarily have to be accompanied by surface band bending in ZnO. Band bending – if it does occur – may be localized to few Å or extend over hundreds of nanometers with very different results for the surface work function and energy level alignment. Managing the delicate balance of different interface manipulation mechanisms in organic–inorganic hybrid systems will be a major challenge towards future applications. Read more .
Read more news
What does ‘quantum’ mean?
Two quantum researchers at Aalto University explain how the seemingly impossible becomes a part of everyday reality.
Samu Taulu develops next-generation brain imaging methods
Associate Professor of neurostimulation and neuroimaging Samu Taulu develops more precise methods for understanding the brain
EAA Best Paper and Presentation Award for Young Researchers for postdoctoral researcher Thomas Deppisch
The awarded work shows how speech can be made clearer in noisy environments while still preserving directional cues