In situ infrared thermographic screening of compositional spread Mg–Ti thin-film libraries

An infrared imaging set-up and our own data treatment methodology have been developed to investigate hydrogen storage properties of combinatorial metallic thin-film libraries in situ. The technique has been tested by analysing the kinetics of hydrogen sorption and desorption in pure metallic magnesium films and in compositional-spread Mg–Ti libraries. Thermography was used to screen the surface emissivity of the libraries, since hydrogenated and dehydrogenated phases present very different values of this property. The proposed data treatment allows for direct visualisation of onset reaction temperatures (Thydrogenation and Tdehydrogenation) in function of composition which, in the present case, clearly reveals the catalytic influence of titanium on the kinetic properties of magnesium film dehydrogenation.

► We have developed and optimised experimental methodology and data treatment for an infrared imaging tool to be used to characterised hydrogenation and dehydrogenation processes in thin film combinatorial libraries.
► Homemade matlab routines allow us to rapidly determine dehydrogenation temperature onsets for any library composition.
► The proof of concept is performed by analysing a compositional graded MgTi thin film library.
► Dehydrogenation temperatures as a function of titanium content are found, confirming the catalytic effect of the titanium doping.