The synthesis of Pd nanoparticles (NPs) in solution and on surfaces through a seed-mediated growth route is reported. For the Pd NPs synthesized in solution, the diameters of the Pd NPs can be readily tuned from 33 to 110 nm, maintaining good monodispersities by using different amounts of ca. 3 nm gold NPs as seeds. The Pd NPs synthesized are polyhedral in shape and are mainly bounded by {111} facets. They also show a much higher intensity ratio of the (111) to (200) diffraction peaks in comparison to that of the JCPDS card 05-0681. When used as surface-enhanced Raman scattering (SERS) substrates, these Pd NPs show different SERS enhancement as a function of their size, Pd NPs of about 62 nm showing the highest SERS enhancement among the three different sizes of Pd NPs employed in this study. The procedure proposed here to grow Pd NPs in solution can also be used to grow small Pd NPs on gold-sputtered substrates, which display facile electrocatalytic ability for O2 reduction.

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The direct electropolymerization of benzene dissolved in the ionic liquid 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate was studied at room temperature applying the electrochemical quartz-crystal microbalance technique. Analysis of the damping changes showed that the Sauerbrey equation could be applied for data evaluation. In the polymer, every third to fourth benzene ring carried a positive charge in the oxidized state. During electropolymerization, some ionic liquid was absorbed in the growing polymer. The redox behavior was characterized by wide peaks typical for conducting polymers. Charge neutrality of the polymer during redox cycling was maintained by anion and cation exchange with the ionic liquid. With increasing scan rate, cation exchange became more and more important.

Thin epitaxial films of the high-perovskite SrHfO 3 were grown by molecular beam epitaxy on Si(100) and investigated by ellipsometry and X-ray photoelectron spectroscopy to determine its band gap and valence band offset. Conducting AFM shows a good correlation between topography and current mapping, pointing to direct tunneling conduction. Long channels MOSFETs with low equivalent oxide thickness (EOT) were fabricated and their channel mobility measured. Mobility enhancement can be achieved by post processing annealing in various gases but at the cost of interfacial regrowth. An alternative approach to increase mobility without changing EOT is by electrically stressing the gate dielectric at ~150 o C.