| AVS 64th International Symposium & Exhibition | |
| Surface Science Division | Monday Sessions |
| Session SS+AS+HC-MoA |
| Session: | Surface Science for Energy and the Environment |
| Presenter: | Sven Pletincx, Vrije Universiteit Brussel, Belgium |
| Authors: | S. Pletincx, Vrije Universiteit Brussel, Belgium L. Trotochaud, Lawrence Berkeley National Laboratory L.-L. Fockaert, TU Delft, Netherlands A.R. Head, Lawrence Berkeley National Laboratory O. Karslıoğlu, Lawrence Berkeley National Laboratory J.M.C. Mol, TU Delft, Netherlands H. Bluhm, Lawrence Berkeley National Laboratory H. Terryn, Vrije Universiteit Brussel, Belgium T. Hauffman, Vrije Universiteit Brussel, Belgium |
| Correspondent: | Click to Email |
Probing interactions at the interface of polymer coatings and passivated metal oxide surfaces under humid conditions has the potential to reveal the local chemical environment at solid/solid interfaces under real-world, technologically relevant conditions. Common surface sensitive analysis techniques only operate under vacuum conditions, making it impossible to probe environmental effects in situ. Stability of formed bonds in aqueous environments between carboxylic acid functional groups of a polymer and a hydroxide surface of aluminum oxide has a great relevance to a broad range of applications. Although this region is very important for understanding adhesion of the polymer coating, it is very challenging to get useful information directly from the solid/solid interface, let alone characterize the effect of water on the formed chemical bonds.
Recent developments in the field of ambient-pressure photoelectron spectroscopy (APXPS) make it possible to set up a novel approach with respect to interface studies. [1] This is done by making the polymer layer sufficiently thin to access the interface with this surface analysis technique. A broad range of relative humidity can be simulated in the analysis chamber, to unravel interfacial chemistry changes of the hybrid system in situ. Here, we show that APXPS with a conventional X-ray source can be used to study the effects of water exposure on the interaction of acrylic coatings with aluminum oxide. [2]
Complementary in situ ATR-FTIR Kretschmann experiments on a similar model system are conducted. An Al layer is sputtered on an IR transparent crystal, the IR signal at the interface is amplified because of the Kretschmann effect and a near-interface spectrum of the oxide/polymer surface is obtained. This way, we have direct access to the interface, and the influence of an above-the-polymer electrolyte (i.e. H2O) can be probed. An integrated setup of ATR-FTIR Kretschmann and Odd Random Phase multisine Electrochemical Impedance Spectroscopy (ORP-EIS) allows to probe the transport of water (and other ions) through the polymer towards the interface. The subsequent interface processes can be followed with infrared spectroscopy while simultaneously the protective properties of the overall hybrid system are studied by ORP-EIS. [3]
[1] D. F. Ogletree, H. Bluhm, E. D. Hebenstreit, and M. Salmeron. Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip., 601, 1–2, 151–160, 2009.
[2] S. Pletincx, L. Trotochaud, L. Fockaert, J.M.C Mol, A. Head, O. Karslıoğlu, H. Bluhm, H. Terryn, T. Hauffman. Sci. Rep.7 (45123), 2017.
[3] M. Öhman and D. Persson, Surf. Interface Anal., 44, 2, 133–143, 2012.