Highly active and stable Pd/MgAl2O4@MgO catalyst with electronic metal-support interaction for selective hydrogenation of isoprene

Electronic metal-support interaction (EMSI) had attracted increasing attention to tailor the electronic and catalytic properties of supported metal catalysts. In this work, we constructed a hierarchical Pd/MgAl2O4@MgO catalyst with flake-like MgO densely distributed on the surface of MgAl2O4. High specific surface MgAl(2)O4@MgO contributed to disperse and stabilize Pd particles and induced EMSI that allowing for electron donation from MgO to Pd. This was identified by the increase of the electronic density of Pd and the changes in CO adsorption behavior. Compared with Pd/MgAl2O4, Pd/MgO and Pd/Al2O3 catalysts, the as-prepared Pd/MgAl2O4@MgO catalyst exhibited significantly higher activity and selectivity with excellent stability for selective hydrogenation of isoprene. The improved catalytic activity and stability could be associated with the electronic and geometric interaction between Pd and MgAl2O4@MgO, which promoted the dissociation of H-2 and weakened the adsorption of semi-hydrogenation products.