Production strategies of tinx coatings via reactive high power impulse magnetron sputtering for selective h2 separation

This scientific work aims to optimize the preparation of titanium nitride coatings for selective H separation using the Reactive High Power Impulse Magnetron Sputtering technology (RHiPIMS). Currently, nitride-based thin films are considered promising membranes for hydrogen. The first series of TiN/Si test samples were developed while changing the reactive gas percentage (N%) during the process. Obtained coatings were extensively characterized in terms of morphology, composition, and microstructure. A 500 nm thick, dense TiN coating was then deposited on a porous alumina substrate and widely investigated. Moreover, the as-prepared TiN films were heat-treated in an atmosphere containing hydrogen in order to prove their chemical and structural stability; which revealed to be promising. This study highlighted how the RHiPIMS method permits fine control of the grown layer's stoichiometry and microstructure. Moreover, it pointed out the need for a protective layer to prevent surface oxidation of the nitride membrane by air and the necessity to deepen the study of TiN/alumina interface in order to improve film/substrate adhesion.