Friction Stir Welding is a relatively new technique for welding that uses a cylindrical pin or nib inserted along the weld seam. The nib (usually threaded) and the shoulder in which it is mounted are rapidly rotated and advanced along the seam.Extreme deformation takes place leaving a fine equiaxed structure in the weld region.

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A class of Pd−Ni−P electrocatalysts are prepared for the ethanol electrooxidation reaction (EOR). Xray diffraction and transmission electron microscope reveal that the synthesized Pd−Ni−P catalyst possesses a more amorphous structure with smaller particle sizes when compared with a Pd−Ni sample without P and a control Pd black (Pd-blk) sample. The Pd−Ni−P catalyst contains double the number of electrocatalytically active sites (12.03%) compared with the Pd−Ni (6.04%) and Pd-blk (5.12%) samples. For the EOR, the Pd−Ni−P catalyst has the lowest onset potential (−0.88 V vs SCE), the most negative peak potential (−0.27 V vs SCE), and the highest EOR activity in 0.1 M KOH solution. Moreover, a 110 mV decrease in overpotential is observed for the EOR on the Pd−Ni−P catalyst compared with the Pd-blk catalyst. A Tafel slope of 60 mV/dec at low polarization potentials (<−0.76 V vs SCE) was obtained for EOR at a Pd−Ni−P-coated electrode with a reaction rate constant of 2.8 × 10 −4 cm•S −1 •M −1 at −0.3 V vs SCE in KOH media. Finally, we find that the electrooxidation of ethanol on the Pd−Ni−P catalyst undergoes a 4-electron process to acetate.

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Photocatalytic assembly of heterometallic nanoarchitectures via plasmonic hot electrons is demonstrated by liquid-phase, reductive photodeposition of platinum (Pt) onto gold nanorods (AuNR) under longitudinal surface plasmon (LSP) excitation. Nucleation of Pt 0 from PtCl 6 2−was initiated by plasmonic hot electrons at the Au surface. Sub-5 nm epitaxial overgrowth of Pt followed a core−shell morphology. Measured 6.5 longitudinal:transversal growth aspect ratio revealed longitudinal growth preferentiality that was consistent with the LSP dipole polarity. In situ spectroscopic monitoring of the photocatalytic growth process permitted real-time feedback into Au surface functionalization with PtCl 6 2− according to 16 nm red-shift in its Cl−Pt ligand-to-metal charge-transfer (L π MCT) band involving ligand π orbitals. Subsequent Pt 0 growth kinetics were tracked using the L π MCT band. Discrete dipole models elucidated evolving lightmatter interactions of Pt-decorated AuNR that were consistent with experimental characterization. These studies provide a foundational mechanistic understanding toward guided assembly of heterometallic nanoarchitectures at ambient conditions via plasmonic hot electrons.