Julia Stähler and Patrick Rinke:
Chem.Phys. 485-486, 149-165 (2017), pp. 17;
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 this energy level alignment at various ZnO surfaces to modications of the potential energy landscape 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 dierent 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.
The original publication is available by link DOI: 10.1016/j.chemphys.2016.11.017