We report the chemical fabrication of metallic glass nanoparticles (MG-NPs). Using commercially available Pd, Ni, and P precursors, size-controlled amorphous Pd–Ni–P NPs were obtained by a one-pot solvothermal synthesis procedure. Differential scanning calorimetry identified typical MG properties of the unsupported Pd–Ni–P NPs with a wide supercooling region of 55 K (602–657 K). Notably, the supported MG-NPs showed remarkable catalytic properties in methanol electro-oxidation in an alkaline medium. After 400 cyclic voltammetry cycles, the loss of current density was only 3.5% when Pd–Ni–P NPs on Vulcan XC-72 were used as a catalyst. This catalytic durability is outstanding compared to those of many other Pd- or Pt-based nanocatalysts, including the recently reported precious Pt–Pd nanomaterials. These results indicate the potential use of Pd-based MG-NPs as fuel cell catalysts.

The ultrafast structural dynamics in the electronic excited state of photoactive yellow protein (PYP) is studied by femtosecond stimulated Raman spectroscopy. Stimulated Raman spectra in the electronic excited state, S(1), can be obtained by using a Raman pump pulse in resonance with the S(1)-S(0) transition. This is confirmed by comparing the experimental results with numerical calculations based on the density matrix treatment. We also investigate the hydrogen-bonding network surrounding the wild-type (WT)-PYP chromophore in the ground and excited states by comparing its stimulated Raman spectra with those of the E46Q-PYP mutant. We focus on the relative intensity of the Raman band at 1555 cm(-1), which includes both vinyl bond C═C stretching and ring vibrations and is sensitive to the hydrogen-bonding network around the phenolic oxygen of the chromophore. The relative intensity for the WT-PYP decreases after actinic excitation within the 150 fs time resolution and reaches a similar intensity to that for E46Q-PYP. These observations indicate that the WT-PYP hydrogen-bonding network is immediately rearranged in the electronic excited state to form a structure similar to that of E46Q-PYP.

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Single-wall carbon nanotubes ͑SWCNTs͒ are attractive components for nanoscale electronics, however their optoelectronic properties have been limited by the optical characteristics of semiconducting SWCNTs. To enhance the functionalities of SWCNTs, ␤-carotene was encapsulated in SWCNTs and its light-harvesting function was investigated. The detailed structure of encapsulated ␤-carotene was clarified using x-ray diffraction and the polarization dependence of the optical absorption spectra. The photoluminescence spectra revealed excited energy transfer from ␤-carotene to the SWCNTs.