The main objective of the proposed project is the development and industry-driven evaluation of highly stable and highly oxygen-permeable nano-structured oxygen transport membrane (OTM) assemblies with infinite selectivity for oxygen separation from air. The new approach proposed to reach this objective is the development of ultra thin membrane layers by e.g. CVD, PVD or Sol-Gel techniques with catalytic activation of the surfaces. This approach is supposed to make available highly stable membrane materials, which are currently out of discussion as the oxygen permeation measured on thick membranes is too low. Sufficiently high oxygen fluxes shall be obtained by (i) ultra thin membrane layers on porous supports to minimize diffusion barriers; (ii) catalytic surface activation to overcome slow surface exchange/reaction kinetics; and (iii) thin-film nano-structuring, generating new diffusion paths through the grain boundaries in a nano-crystalline matrix. The membrane development is supported by thermo-mechanical modelling as well as atomistic modelling of transport properties. The produced oxygen is provided to Oxyfuel power plants or chemical processes such as oxidative coupling of methane (OCM) to higher hydrocarbons or HCN synthesis, which will contribute in a way to the mitigation of CO2 emissions. Oxyfuel power plants combust fuels using pure oxygen forming primarily CO2 and H2O making it much easier and cheaper to capture the CO2 than by using air. The major advantages of OTM are significantly lower efficiency losses than conventional technologies and the in principle infinite oxygen selectivity. OCM produces higher hydrocarbons directly without forming CO2 and HCN synthesis can be improved by process intensification resulting in energy and subsequent CO2 savings.