Operando Spectroscopic studies for CO2 to fuels

The research activity performed during this period has been focused towards the study of the CO2 hydrogenation reaction mechanism to dimethyl ether (DME) production by exploiting the potential of DRIFT in "operando mode" and "in situ" XPS measurements. Specifically, by employing DRIFT, the measurements have been carried out under the real reaction conditions, in the temperature range of 180-260°C under pressure. The aim of the research activity was to individuate the nature and the functionality of surface adsorption sites, determine the intermediate compounds formed and evaluate how the CO2 is activated on Cu-zeolite based catalysts to be then converted to DME in order to further optimize the formulation and the design of the solid Cu-based catalysts. In situ XPS measurements contributed to highlight the chemical state of species present on the solid catalysts thus allowing defining the role of each active site which determines the catalytic behavior of different catalysts investigated. At the same time, surface acidic properties were evaluated by pyridine adsorption used as a probe molecule and further characterization of "fresh" and "used" catalysts were carried out by using XRD and UV-VIS techniques.