Preparation and catalytic properties of pd/PAMAM[poly(amido amine)]/SBA-15 catalyst

Pd/PAMAM dendrimers nanoparticles (Pd DEN) with tunable size were prepared by Poly(amidoamine) (PAMAM) dendrimers-templated method, then Pd DEN were immobilized on SBA-15 by ultrasonic method to obtain SBA-15 supported Pd dendrimers nanoparticles (Pd SDEN). TEM and XRD results indicate that the parent structures of Pd nanoparticles and SBA-15 are well-maintained during the supporting process and Pd nanoparticles are highly dispersed inside the channels of SBA-15. The catalytic activity was studied by monitoring the reduction of p-nitrophenol photometrically. The results indicate that the catalytic activity of Pd SDEN is significantly enhanced compared to that of the corresponding DEN. The catalytic activity of the catalyst is well maintained after five cycles, resulting in the reaction rate reduced by only 4% and Pd DEN particles are still stable in the pores of zeolite.