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The effect of para-substituents on the NC bond of aryl isocyanide molecules adsorbed on Au, Ag, Pt, and Pd surfaces was examined by vibrational sum frequency generation (VSFG) spectroscopy. The frequency of NC stretching vibration, υNC, depended on the electronic property of the substituents. When the substituents were more electron-withdrawing and more electron-donating, υNC shifted to lower and higher frequencies, respectively. However, υNC shifted to lower frequency again when the substituents were too electron-donating. The strong dependence of υNC on metal substrates was also observed, reflecting the difference in metal d-band energies, which leads to the difference in the contributions of σ-donation and π back-donation of the NC–metal coupling. [ABSTRACT FROM AUTHOR]

Anode-free lithium metal batteries (AFLMBs) have attracted great attention owing to their higher energy density compared to conventional lithium metal batteries. Unfortunately, AFLMBs still suffer from poor Coulombic efficiency (CE) due to severe dendrite growth and the unstable solid–electrolyte interface (SEI) at the anode. Therefore, we explored the effect of concentration and LiNO3 additive on the SEI layer and on Li plating/stripping efficiency using a low-concentration tetraethylene glycol dimethyl ether (TEGDME)-based electrolyte in an AFLMB anode half-cell configuration. It was found that the formation of protective Li2O-based SEI layers when blocking the oxidative subsequent SEI formation (called "OSS") above 2.2 V vs. Li/Li+ improved Li plating/stripping stability, while the LiNO3 additive suppressed the oxidation of Li2O into Li2O2 and sustained the existence of Li2O without blocking OSS, therefore improving CE performance. Although increasing the concentration (from 0.4 M to 2.0 M) did not have a major effect, the 2.0 M electrolyte with LiNO3 additive shifted the dominant SEI species from Li2O to LiF, further enhancing CE performance. [ABSTRACT FROM AUTHOR]

Electrocatalytic activities for the oxygen reduction reaction (ORR) of Au electrodes modified by as prepared and size selected (0.45–1.0, 0.22–0.45, and 0.1–0.22 µm) h-BN nanosheet (BNNS), which is an insulator, were examined in O2 saturated 0.5M H2SO4 solution. The overpotential was reduced by all the BNNS modifications, and the smaller the size, the smaller the overpotential for ORR, i.e., the larger the ORR activity, in this size range. The overpotential was reduced by as much as ∼330 mV compared to a bare Au electrode by modifying the Au surface by the BNNS of the smallest size range (0.1–0.22 µm). The overpotential at this electrode was only 80 mV more than that at the Pt electrode. Both the rotation disk electrode experiments with Koutecky–Levich analysis and rotating ring disk electrode measurements showed that more than 80% of oxygen is reduced to water via the four-electron process at this electrode. These results strongly suggest and theoretical density functional theory calculations support that the ORR active sites are located at the edges of BNNS islands adsorbed on Au(111). The decrease in size of BNNS islands results in an effective increase in the number of the catalytically active sites and, hence, in the increase in the catalytic activity of the BNNS/Au(111) system for ORR. [ABSTRACT FROM AUTHOR]

Anode‐free lithium‐metal batteries (AFLMBs) are regarded as a promising candidate for next‐generation batteries due to a great enhancement of energy density over lithium‐metal anode batteries. However, unstable solid‐electrolyte interface (SEI) formation accompanied by lithium dendrite growth and electrolyte decomposition causes low Coulombic efficiencies. This study explores the effect of different operating potential ranges on SEI layer structure and further on Li plating/stripping efficiency in the dilute LiTFSI/TEGDME electrolyte in an AFLMB anode half‐cell configuration. Cyclic voltammetry analyses reveal the existence of an "oxidative subsequent SEI" formation process (named as OSS) and the improved Li plating/stripping efficiency by blocking reaction OSS, which is further verified by quartz crystal microbalance analysis regarding the insight of such an improvement. XPS depth‐profile analysis confirms the formation of the Li2O‐ and lithium‐sulfur compounds‐based subsequent SEI layers when the OSS process is blocked, which guarantees the improved stability of Li plating/stripping. A hypothesis is proposed to discuss possible electrochemical reactions via OSS process by combining in situ surface‐enhanced Raman spectroscopy analysis. These results together suggested the importance of adjusting operating potential range in a proper manner to achieve a better performance in Li plating/stripping in AFLMB configuration. [ABSTRACT FROM AUTHOR]

The article An approach to the research on ion and water properties in the interphase between the plasma membrane and bulk extracellular solution, written by Hiroshi Hibino, Madoka Takai, Hidenori Noguchi, Seishiro Sawamura, Yasufumi Takahashi, Hideki Sakai and Hitoshi Shiku, was originally published Online First without open access., Author(s): Hiroshi Hibino[sup.1,2,3], Madoka Takai[sup.4], Hidenori Noguchi[sup.5], Seishiro Sawamura[sup.1], Yasufumi Takahashi[sup.6,7], Hideki Sakai[sup.8] and Hitoshi Shiku[sup.9] Erratum to: J Physiol Sci (2017) 67:439-445 DOI 10.1007/s12576-017-0530-3 The article 'An approach to [...]

Carboxylic acid-terminated monolayers on crystalline silicon surfaces are prepared by acid-catalyzed hydrolysis of alkoxycarbonyl (ester)-terminated monolayers and its structures are studied by vibrational sum frequency generation (SFG) spectroscopy. The results show that SFG is capable of providing quantitative information on structure-reactivity correlations in organic monolayers.

Olefins adsorbed on Bronsted acidic hyrdroxyl groups (OD) of DM20 zeolite by transient infrared absorption spectral after excitation or the OD stretching mode using picosecond infrared lasers are investigated. The adsorbed olefins are ethylene, ethylene-d, propylene and isobutene and their adsorption forms are methyl adsorption for isobutene and pi-adsorption for the other olefins.