We prepared phthalate derivatives based flexible electrochromic (EC) cell with gel electrolyte containing DMSO solvent in order to improve memory properties. The cell showed vivid color change from water transparent to three primary colors by electrochemical reduction as similar to the liquid electrolyte cell reported previously. The cell exhibited better coloring and memory properties than the cell containing NMP solvent. The apparent diffusion coefficient for the electron transfer of dimethyl terephthalate (DMT) which shows magenta-color EC is estimated to be 10−6 cm2/sec with chronoamperometric measurement. It is revealed that the DMSO is effective to stabilize the anion radicals of DMT rather than NMP.
We obtained mono-dispersed spherical LiMn2O4 particles via spherical MnCO3 intermediate material by coprecipitation method that was one of soft chemical techniques. We fabricated a sintered type porous electrode that consisted only of active material. The electrochemical characteristics of prepared sintered electrode were compared with general composite electrode including conducting material and binding material. The discharge capacity and average discharge voltage of the sintered electrode were relatively higher than those of the composite electrode. It is suggested that an internal resistance of the sintered electrode is lower. Here, we propose that the simplification using the sintered electrode is useful for understanding behavior of rechargeable lithium ion batteries by means of mathematical simulation.
We have already reported about the performance of active carbon adsorbed with Cu(II)-picolinic acid complex. The capacitor showed higher capacitance than normal activated carbon. In this report, we have used another kind of AC and electrolyte. We could observe it’s accurate oxidation-reduction reaction by cyclic voltammetry and constant current electrolysis. We also comfirmed Cu(II)-picolinic acid complex’s disorption from the AC in the 4 M H2SO4/H2O. The cause of disorption is form of Cu(II)-picolinic acid in the low pH. We change electrolyte into 3.5 M NaBr/H2O and the disorption is suppressed.
A glucose-sensing electrode based on the cathodic detection of oxygen, which was consumed with the glucose oxidase-catalyzed reaction in the presence of glucose, was prepared by immobilizing the enzyme on a surface-modified poly(dimethylsiloxane) (PDMS) layer. A PDMS layer was prepared on a platinum electrode by casting an emulsion of the polymer, the polymer surface was treated with oxygen plasma to replace silane groups with silanol groups, and then a GOx layer was prepared on the PDMS layer by applying silanization and cross-linking chemistries. The oxygen plasma-treatment of PDMS did not cause significant changes in the permselectivity with the polymer layer so as to discriminate hydrophilic solutes, such as hydrogen peroxide, from oxygen. Thus, the resulting electrode could be used for the measurement for glucose (0.02–1.8 mM) without the error caused by L-ascorbic acid and uric acid.
Until the mid 1980’s, there had been only few in situ methods available for structural determination of an electrode surface in solution at atomic and monolayer levels. Nowadays, many powerful in situ techniques, such as electrochemical scanning tunneling microscopy (EC-STM), infrared reflection absorption spectroscopy (IRAS), surface-enhanced Raman scattering (SERS), and surface-enhanced infrared reflection absorption spectroscopy (SEIRAS), second harmonic generation (SHG), sum frequency generation (SFG), and surface X-ray scattering (SXS) have been widely employed to characterize the electrode surfaces under potential control with atomic and/or molecular resolution. The object of this review is to highlight some of the progress on in situ methods at solid-liquid interface with atomic and molecular levels. Several selected topics are focused on, specifically adsorbed anions on metal surface, electrocatalysis of the carbon oxide oxidation and xygen reduction, and direct observation of single crystal electrode surfaces.