(574a) Synthesis, Physical Characterization and Hydrogen Generation by Methanol Dry Reforming Over Silica-Supported Size-Controlled Pd Nanoparticles

In the efforts to create and optimize supported nanoscale catalysts for use in the generation of renewable fuels, the beneficial effects of tuning the sizes and shapes of the catalysts have been actively studied. Due to the impact that the size and shape of the nanoparticle has on the surface energy potentials, and thus the particles’ activity, the ability to control the particles’ shape and size would be a very beneficial tool in catalyst development.

     Here we report the synthesis, physical characterization and catalytic testing of silica-supported size-controlled Pd nanoparticles of 4 to 16 nm average diameter. The nanoparticles were synthesized using a one-pot polyol method and then immobilized by depositing onto a CAB-O-SIL® M-5 Silicon dioxide support. The size of the nanoparticles synthesized was controlled by using two precursors of different oxidation states in varying set molar ratios. Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD) were used to measure the sizes of the nanoparticles. The catalytic activity of the supported particles was studied by running methanol dry reforming under temperature programmed reaction spectroscopy after pretreatment under oxidizing conditions at 623 K. The methanol dry reforming reaction was found to be structure-sensitive on the particles, with the peak TOF going through a maximum over the 6 nm particles.