A new approach to chemical imaging was reported by the group of Umezawa in 1998, utilizing scanning tunneling microscopy (STM) with chemically modified tips. Just as in electrochemistry, electron transfer through the overlap of electronic wave functions of tip and sample surfaces plays a central role in STM, which relies on the tunneling effect as operating principle. This similarity and the success of chemically modified electrodes suggested us that "tailored" chemical modification of STM tips should allow the control of electron tunneling through rational use of chemical interactions. The chemical imaging was obtained from a distinctive chemical affinity between the imaging tip and the substrate, such as hydrogen bond and metal coordination interactions that enhanced the electron tunneling. This technique allows imaging of specific surface species at atomic/molecular resolution and will become a powerful method for fundamental chemical studies at molecular level.

Electrochemical behavior of oxide ion at a glassy carbon electrode in a LiF-NaF-KF eutectic melt was investigated by cyclic voltammetry and chronopotentiometry at 753-823 K. The gases produced by potentiostatic electrolysis at 3.0 V (vs. K⁺/K) were confirmed as CO₂ and CO by IR spectroscopy and gas chromatography. The anodic reaction of oxide ion was found to be an irreversible process. The diffusion coefficient of oxide ion as a function of temperature was expressed as: D_O²⁻ = 1.3×10^-2 exp(−3.9×10⁴/RT)cm² s^-1. The potential sweep method was proved to be useful for monitoring the oxide ion concentration.

The oxygen reduction on Ag electrode in the alkaline solution has been investigated by a channel flow double electrode (CFDE). The HO₂^- emitted from the Ag working electrode can be detected by the collecting electrode at the downstream of the working electrode. The average number of electron transfer n̅ in oxygen reduction was determined from the working and collecting electrode currents of CFDE. The final products of the oxygen reduction on the polished Ag electrode in the alkaline solution are OH^- and HO₂^-, and the values of n̅ are between 2 and 4. In the present paper, it was found that the n"̅ is close to 4 on Ag electrode pre-oxidized at the potential for AgO formation. The influence of pre-oxidation for Ag electrode on n̅ has been discussed. Furthermore, electrochemical impedance was measured to investigate the surface condition of the pre-oxidized Ag electrode. The electrochemical impedance of Ag during oxygen reduction shows an inductive semicircle on the complex plane, indicating the indirect 4-electron reduction.

We performed a cycle test with 25% and 40% depth of discharge (DoD) using 30 Ah prismatic Lithium-Ion secondary cells designed for ground applications. For 25% DoD, we observed adequate cycle performance exceeding 18,000 cycles. For 40% DoD, the end of discharge voltage (EoDV) decreased to 3.0 volt after 10,000 charge-discharge cycles, which enabled us to disassemble the cell and check the reason of performance degradation. Through the analysis, we found that the reduced cell performance mainly caused by capacity loss in the negative electrode, especially in the middle of the cell stack. The positive electrode also degraded slightly, and the impedance of the positive electrode increased. The discharge capacity during the 40% DoD test might not be restored by simulated low Earth orbit cycling because of these degradations.

Temperature effect on methanol and ethanol electrooxidation was investigated with cyclic voltammetry at carbon supported Pt and Pt-Ru microporous electrodes. In methanol solution, the currents were enhanced by 10 and 20 times at Pt/C and Pt-Ru/C, respectively in the temperature range from 25°C to 80°C. With increasing temperature at both electrodes, decreases in the potential difference of oxidation peaks at positive and negative potential scanning were observed, indicating that OH adsorption on the catalysts affects methanol oxidation and bifunctional mechanism is active. Especially, vertically increased oxidation peak during negative potential scanning was observed at Pt/C, presumably due to the weak OH adsorption on the platinum surface. The effect of ruthenium addition on the poisoning reduction was also confirmed. In ethanol solution, Pt/C increased currents only by a factor of 4 whereas Pt-Ru/C raised it about 8 times for the same temperature range. Lower temperature dependence of currents in the ethanol solution is probably caused by weaker OH adsorption in the ethanol solution than in the methanol solution. The ruthenium addition remarkably enhanced ethanol oxidation performance probably due to the strong adsorption of OH. In both alcohols, Pt-Ru/C showed larger apparent activation energies of oxidation than Pt/C, representing higher temperature dependence of OH adsorption on ruthenium.

Scanning Electrochemical Microscope (SECM) has been applied to study pitting corrosion of iron in a 50 mM NaCl solution at pH 8.4. In order to monitor pitting propagation, a platinum wire of 10 μm in diameter sealed in Pyrex glass tube was used as an ultra micro probe (tip electrode). In order to detect Fe³⁺ ion flux emitted from a pit mouth, the tip electrode was placed 5 μm above the pit and polarized at −0.4 V vs. Ag/AgCl/3 M KCl reference electrode so that the Fe³⁺ ion is reduced to Fe²⁺ on the surface. The Fe³⁺ ion was successfully detected on the tip electrode surface.