TY - JOUR A1 - Gossenberger, Florian A1 - Roman, Tanglaw A1 - Forster-Tonigold, Katrin A1 - Groß, Axel T1 - Change of the work function of platinum electrodes induced by halide adsorption JF - Beilstein Journal of Nanotechnology PY - 2014/// VL - 5 SP - 152 EP - 161 SN - 2190-4286 DO - 10.3762/bjnano.5.15 PB - Beilstein-Institut JA - Beilstein J. Nanotechnol. UR - https://doi.org/10.3762/bjnano.5.15 KW - density functional theory KW - ionicity KW - polarizability KW - surface dipole KW - work function N2 - The properties of a halogen-covered platinum(111) surface have been studied by using density functional theory (DFT), because halides are often present at electrochemical electrode/electrolyte interfaces. We focused in particular on the halogen-induced work function change as a function of the coverage of fluorine, chlorine, bromine and iodine. For electronegative adsorbates, an adsorption-induced increase of the work function is usually expected, yet we find a decrease of the work function for Cl, Br and I, which is most prominent at a coverage of approximately 0.25 ML. This coverage-dependent behavior can be explained by assuming a combination of charge transfer and polarization effects on the adsorbate layer. The results are contrasted to the adsorption of fluorine on calcium, a system in which a decrease in the work function is also observed despite a large charge transfer to the halogen adatom. ER -