Berlin 2015 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 14: Oxide Surfaces: Adsorption and Reactivity
O 14.10: Vortrag
Montag, 16. März 2015, 17:15–17:30, MA 042
Formation of dendritic structures due to water ice on oxide surfaces under ambient conditions — •Oğuzhan Gürlü1, Kivanç Esat1, and Özgür Birer2 — 1Istanbul Technical University, Istanbul, Turkey — 2Koç University, Istanbul, Turkey
We have studied the chemical and morphological properties of nanoscale chromium oxide particles on glass and silicon oxide surfaces. Furthermore we investigated their interaction with water from the ambient atmosphere. We found out that dendritic structures due to water on these surfaces can from spontaneously. Our systematic studies of dosing such surfaces with humidified air revealed formation of further fractal structures due to water condensation and evaporation. The growth of these structures was observed under an ambient optical microscope in real time. When these samples were transferred to an atomic force microscope (AFM), dendrites due to water ice could still be observed, also under ambient conditions. AFM data showed that these structures could be as high as several hundredths of nanometers, proving them to be three-dimensional. Depending on the density of the oxide particles on glass or silicon oxide surfaces, shapes and sizes of the dendrites were observed to differ. Despite the counter intuitive nature of such formations, an explanation could be brought to their formation by use of Electrostatic Force Microscopy (EFM).