UNVEILING THE IMPACT OF DOPING IONS ON ALUMINIUM OXIDE AS AUTOMOTIVE CATALYST SUPPORT

Aluminium oxide has been widely adopted as catalyst support for gas exhaust abatement in the automotive field. The role of the support is crucial for the catalyst design since it enhances the stabilisation of the catalyst, avoiding sintering tendency of the catalytic particles. This Master Thesis project, carried out in tight cooperation with Umicore R&D Department in Hanau (Germany), aimed at understanding how doping species such as phosphates, zirconium and lanthanum affected the physical properties of alumina and the catalyst perfomances. Doped aluminium oxide was synthesised by a sol-gel route, varying parameters, like temperature, time and dopant amount. The characterisation of the obtained materials was performed using a rich tool-box of analytical methods, such as XRD, BET, SEM-EDX, FT-IR in order to get a comprehensive insight into of the material properties. Selected samples were then tested as catalyst support for Pt nanoparticles for exhaust gases abatement. The tests were performed at dedicated facilities by Umicore. The results of the catalytic tests highlighted that the doped samples promote the conversion temperature of CO and propylene at lower temperature with respect to pure alumina, therefore showing better activity. This behaviour was found both in fresh and aged samples.