Perfluoroalkyl substances (PFASs) are stable, surface active and fully fluorinated compounds that have both a hydrophobic fluorinated carbon chain and a hydrophilic ionizable functional group. The stability of PFASs has implications when it comes to the environment, as they are non-reactive, and not readily biodegradable. The leaching and availability of PFASs in soil is controlled by the extent of adsorption to soil particles, and there is a great demand for more knowledge about the adsorption behavior of PFASs to solid/liquid interfaces. The present proposal aims to investigate the interactions of PFASs with a solid sapphire interface, with focus on the effect of varying chain length.