This group is part of the Membrane Science & Technology Cluster. The focus on the synthesis and of thin (hybrid) films by locally controlled chemistry, and the in-situ characterisation of these films under relevant conditions. The foreseen applications revolve around membrane separations under demanding conditions, for instance high-T,p gas separation and nanofiltration of mixtures containing organic molecules or extreme pH. In contrast to relying on empirical relations between performance, process conditions, and membrane materials, we aim to deconvolute the underlying effects of intrinsic materials properties, length scale, time scale, support effects. For this, we study directly the properties of thin films that are exposed to fluids, using techniques such as spectroscopic ellipsometry, quartz crystal microbalance, and broadband dielectric spectroscopy.