Anodic dissolution of zirconium in Bun4NBr-containing n-butanol solutions was investigated using cyclic voltammetry, linear sweep voltammetry and potentiostatic current–time transient and scanning electron microscopy (SEM). Zirconium did not exhibit active dissolution due to passivation in the potential region of 0.2 to 1.2 V vs. SCE. The zirconium dissolution in passive state was under mass transfer control. Pitting corrosion took place as a result of passivity breakdown by Br− anions and the typical steady-state pitting potential was between 1.55–1.60 V vs. SCE in n-butanol solutions containing 0.08 M Bun4NBr. SEM images confirmed the occurrence and the intensification of pits with an increase of potential. Increasing Bun4NBr concentration accelerated the pit nucleation and growth. The reaction order leading to pit nucleation process was 1.0 with respect to bromide anions. The dissolution of zirconium in n-butanol solution produced Zr(OC4H9)4.
The effects of preparing condition on crystallographic orientation for electrodeposited aluminum from the plating solution with aluminum chloride (AlCl3) and dimethyl sulfone (DMSO2) were investigated. The molar ratio of DMSO2:AlCl3 was controlled from 10:1 to 10:5. The temperature range of the solution was from 110 to 150°C. The current density was set from 300 to 600 A/m2. The crystallographic orientation of the samples was strongly influenced by the solution composition and temperature. The films from the solution with ratio of 10:3 exhibited the highly (200) preferred orientation. On the other hand, current density hardly affected the crystallographic orientation within our current density range. The crystallographic orientation is discussed by means of the Pangarov’s model based on the two-dimensional nuclei theory.
Adenosine is known to be a corrosion inhibitor for Fe-based metal. We report the real-time mass change due to the adsorption of adenosine molecules/complex on iron in HCl solution using the quartz crystal microbalance. It is proposed that the adsorption process of adenosine molecules/complex could happen along with iron dissolution process at rest potential. During polarization measurement, the mass loss of the surface of iron was positively related to the resistance of the solution with adenosine. It is believed that during the anodic reaction, the mass loss was caused by desorption of the pre-adsorbed adenosine molecules and also iron dissolution.
The electric double layer capacitor accumulates its electric charge at the electric double layer formed at the vicinity of the each electrode, i.e. cathode and anode. That consists of activated carbon with a large specific surface area. We have already reported that the addition of pseudo-capacity by surface adsorption onto the activated carbon by the hydroquinone or copper picolinate complex. In this report the enlargement characterization of the capacity was investigated by AC impedance method. As a result, in the case of Cu complex adsorbed ACF, in the sulfuric acid electrolyte, the transition frequency shows larger values comparing to none adsorbed one. But in the case of Cu complex adsorbed ACF in the sodium bromide aqueous solution, the frequency shows smaller values comparing to none adsorbed one. On the other hands, hydroquinone adsorbed ACF showed larger transition frequency comparing to none adsorbed one.
In order to improve the ionic conductivity of NASICON-type lithium ion conductor, Li1.3Al0.3Ti1.7(PO4)3 (LATP), lithium ion conductive composites have been prepared to disperse the perovskite-type lithium ion conductor, Li0.348La0.55TiO3 (LLTO), in the LATP matrix. X-ray powder diffraction revealed that the added LLTO has reacted with LATP to form some LaPO4 derivatives after the sintering at 1000°C. The measured conductivity of the composite increases with the amount of added LLTO up to 4 wt% showing the highest value of 7.6 × 10−4 S cm−1, which is approximately three times larger than that of pristine LATP. Further amount of LLTO addition gives gradual decrease in conductivity due to the deterioration of sintered density. It is also confirmed that the transport number of lithium ion is almost unity for the LATP-LLTO composite from the DC conduction experiments using blocking electrode.
A fully-additive fine pattern plating process is described for transparent conductive mesh formation on selectively UV-modified films by electroless copper plating. The reactions of surface modification were considered based on chemical and elemental analysis using X-ray photoelectron spectroscopy (XPS) and surface energy analysis. UV-modified surfaces were created with a polar protic moiety enriched surface that was roughened on the nanometer scale. Furthermore, amplified palladium adsorption selectivity at the modified regions and suppressed deposition on non-modified substrate regions enhanced the resolution. Copper mesh pattern formed on the palladium catalyst pattern achieved lower sheet resistance than indium tin-doped oxide (ITO) film of the same total light transmittance. After annealing the electrolytic plated film, the vertical peel strength between the PEN film and copper deposit was enhanced.