Wu, P. W.; et al., "The influences of surface treatment and gas annealing conditions on the inversion behaviors of the atomic-layer-deposition Al2O3/nIn0.53Ga0.47As metal-oxide-semiconductor capacitor," Appl. Phys. Lett. 97, 042903 (2010); http:// dx

Fabrication of multi-element nanoparticles on noncatalyzed gas diffusion electrodes (GDEs) by radio frequency sputter deposition was reported. X-ray diffraction analysis of the as-deposited films indicated crystalline fcc phases while energy dispersive X-ray spectroscope confirmed their composition as Pt 50 Fe 11 Co 10 Ni 11 Cu 10 Ag 8. Scanning electron microscopy images revealed nanoparticulate nodules growing on the carbon particles. Cyclic voltammetry (CV) was employed to analyze their methanol oxidation abilities for direct methanol fuel cells. The CV responses improved upon cycling and became stabilized after 70 cycles. The areas under the CV curves were proportional to the amount of nanoparticles deposited. In mass activities the GDE with 5 nm nanoparticles demonstrated the highest values of 400-600 mA/mg. In comparing with Pt and Pt 43 Ru 57 , the Pt 43 Ru 57 exhibited the lowest onset potential with the highest mass activities. Our work presents preliminary information on the catalytic behaviors of multi-element nanoparticles which is likely to bring new directions in catalyst design.

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Two‐photon lithography has been used to create a three‐dimensional metallic structure for the first time. A porous gel filled with AgNO3 solution was laser irradiated in a multi‐photon process that allowed silver nanocrystals to be written only on the interior of the gel, resulting in the macroscopic three‐ dimensional spiral shown in the Figure.

Proton exchange membrane fuel cells (PEMFCs) have attracted much attention as an alternative source of energy with a number of advantages, including high efficiency, sustainability, and environmentally friendly operation. However, the low kinetics of the oxygen reduction reaction (ORR) restricts the performance of PEMFCs. Various types of catalysts have been developed to improve the ORR efficiency, but this problem still needs further investigations and improvements. In this paper, we propose advanced Os/Pt core−shell catalysts based on our previous study on segregation of both bare surfaces and surfaces exposed to ORR adsorbates, and we evaluate the catalytic activity of the proposed materials by density functional theory (DFT). Quantum mechanics was applied to calculate binding energies of ORR species and reaction energy barriers on Os/Pt core−shell catalysts. Our calculations predict a much better catalytic activity of the Os/Pt system than that of pure Pt. We find that the ligand effect of the Os substrate is more important than the lattice compression strain effect. To validate our DFT prediction, we demonstrate the fabrication of Os/Pt core−shell nanoparticles using the underpotential deposition (UPD) technique and succeeding galvanic displacement reaction between the Pt ions and Cu-coated Os nanoparticles. The Os/Pt/C samples were evaluated for electrocatalytic activities toward the ORR in acidic electrolytes. The samples with two consecutive UPD-displacement reaction cycles show 3.5 to 5 times better ORR activities as compared to those of commercially available Pt/ C. Our results show good agreement between the computational predictions and electrochemical experimental data for the Os/ Pt core−shell ORR catalysts.