Dresden 2017 – wissenschaftliches Programm
MM 28.6: Vortrag
Dienstag, 21. März 2017, 11:30–11:45, IFW D
Modeling hydrogen diffusion in amorphous and polycrystalline thin films of tungsten trioxide — •Simon Burkhardt1, Matthias Thomas Elm1,2, and Peter Jens Klar1 — 1Heinrich-Buff-Ring 16, 35392 Giessen — 2Heinrich-Buff-Ring 17, 35392 Giessen
The mandatory development of efficient energy management also will advance the commercialization and industrialization of electrochromic fenestration. Most of these devices are based on the electrochromic behavior of thin films such as tungsten trioxide (WO3) induced by reversible insertion and extraction of ions and electrons into the films. A consistent fundamental understanding of the coloration processes is still lacking up to now but is needed to systematically enhance device performance and to increase their cyclability. To elucidate the transport behavior of protons and electrons in WO3 thin films, we performed spatially and temporally resolved in situ transmission measurements on lithographically structured samples during electrochemical hydrogen insertion into amorphous and polycrystalline thin films. The experimental results show a significant influence of film morphology on lateral hydrogen diffusion and are compared with different simulations of theoretical models. These models are based on one dimensional diffusion problems in different continuous media and describe the experimental data qualitatively very well.