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The cathode surface of sulfide‐based all‐solid‐state batteries (SBs) is commonly coated with amorphous‐LiNbO3 in order to stabilize charge–discharge reactions. However, high‐voltage charging diminishes the advantages, which is caused by problems with the amorphous‐LiNbO3 coating layer. This study has investigated the degradation of amorphous‐LiNbO3 coating layer directly during the high‐voltage charging of SBs. O2 generation via Li extraction from the amorphous‐LiNbO3 coating layer is observed using electrochemical gas analysis and electrochemical X‐ray photoelectron spectroscopy. This O2 leads to the formation of an oxidative solid electrolyte (SE) around the coating layer and degrades the battery performance. On the other hand, elemental substitution (i.e., amorphous‐LiNbxP1‐xO3) reduces O2 release, leading to stable high‐voltage charge–discharge reactions of SBs. The results have emphasized that the suppression of O2 generation is a key factor in improving the energy density of SBs. [ABSTRACT FROM AUTHOR]

Identification of small-molecule ligands for a protein of interest can facilitate the analysis of the protein's functions in biological systems. Small-molecule microarrays have allowed for rapid detection of such ligand--protein interactions in a high-throughput manner, although a label on a protein is needed to observe these interactions. By combining SPR imaging technology with our recently developed photo-cross-linked small-molecule array platform, we developed a novel platform that allows in situ observation of interactions between photo-cross-linked small molecules on gold surfaces and nonlabeled proteins in solution. Interactions of estrogenic and androgenic substances with estrogen receptor a were observed using this platform.

A stepwise ion-exchange/reduction approach is used to prepare Ag-Pd bimetallic nanoparticles directly in ultrathin TiO2-gel films. For hydrogenation of methyl acrylate, the catalytic activity of the Pd-on-Ag nanoparticle is 367 times as large as that of commercial Pd black and 1.6 times as large as that of Pd monometallic nanoparticle.

The rectifying electric ferromagnetic resonance spectroscopy was performed to examine the magnetization dynamics in the stripe magnetic domain structure induced by the competition between shape and heterojunction-induced magnetic anisotropy. The observed angle dependence is in good agreement with the analytical calculations based on the macro-spin model when the applied magnetic field is larger than the effective magnetic anisotropy field. When the external magnetic field is smaller than the threshold field at which destroys the stripe domain structure is destroyed, a large rectifying amplitude is generated in a Ni wire aligned perpendicular to the x-axis of the substrate. The relatively large response is attributed to that the coupled oscillations of the stripe domains. In addition, the Gilbert damping factor is found to be enhanced in the system because of stripe domain structure formation and strain-induced modulation. [ABSTRACT FROM AUTHOR]

One of the key challenges when developing magnesium rechargeable batteries (MRB) is to develop Mg-intercalation cathodes exhibiting higher redox potentials with larger specific capacities. Although Mg-transition-metal spinel oxides have been shown to be excellent candidates as MRB cathode materials by utilizing the valence change from trivalent to divalent of transition metals starting from Mg insertion, there is no clear evidence to date that Mg can be indeed extracted from the initial spinel hosts by utilizing the change from trivalent to quadrivalent. In this work, we clearly present various experimental evidences of the electrochemical extraction of Mg from spinel MgMn2O4. The present electrochemical charge, i.e., extraction treatment of Mg, was performed in an ionic liquid at 150 °C to ensure Mg hopping in the spinel host. Our analyses show that Mg can be extracted from Mg1−xMn2O4 up to x = 0.4 and, afterwards, successively be inserted into the Mg-extracted (demagnesiated) host via a two-phase reaction between tetragonal and cubic spinels. Finally, we also discuss the difference in electrochemical features between LiMn2O4 and MgMn2O4. [ABSTRACT FROM AUTHOR]

The interaction between C60 and Si atoms has been investigated for Si atoms adsorbed on a C60 film using in situ x-ray photoelectron spectroscopy (XPS) and density-functional (DFT) calculations. Analysis of the Si 2p core peak identified three kinds of Si atoms adsorbed on the film: silicon suboxides (SiOx), bulk Si crystal, and silicon atoms bound to C60. Based on the atomic percent ratio of silicon to carbon, we estimated that there was approximately one Si atom bound to each C60 molecule. The Si 2p peak due to the Si–C60 interaction demonstrated that a charge transfer from the Si atom to the C60 molecule takes place at room temperature, which is much lower than the temperature of 670 K at which the charge transfer was observed for C60 adsorbed on Si(001) and (111) clean surfaces [Sakamoto et al., Phys. Rev. B 60, 2579 (1999)]. The number of electrons transferred between the C60 molecule and Si atom was estimated to be 0.59 based on XPS results, which is in good agreement with the DFT result of 0.63 for a C60Si with C2v symmetry used as a model cluster. Furthermore, the shift in binding energy of both the Si 2p and C 1s core peaks before and after Si-atom deposition was experimentally obtained to be +2.0 and -0.4 eV, respectively. The C60Si model cluster provides the shift of +2.13 eV for the Si 2p core peak and of -0.28 eV for the C 1s core peak, which are well corresponding to those experimental results. The covalency of the Si–C60 interaction was also discussed in terms of Mulliken overlap population between them. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]