External Voltage (external + voltage)

Distribution by Scientific Domains


Selected Abstracts


Current-Free Deposition of Prussian Blue with Organic Polymers: Towards Improved Stability and Mass Production of the Advanced Hydrogen Peroxide Transducer

ELECTROANALYSIS, Issue 3-5 2009
Anastasiya
Abstract We report on a novel approach for open-circuit (current-free) deposition of Prussian blue. Synthesis of Prussian blue is carried out by reduction of ferric ferricyanide with organic molecules, which are known to form polymers upon oxidation. The proposed interfacial deposition is a result of the synthesis in the presence of electrode support due to preconcentration of precursors at the interface. The resulting modified electrodes displayed the dramatically improved operational stability in hydrogen peroxide continuous monitoring with no loss of either electrochemical or analytical performance characteristics compared to electrodes with electrochemically deposited Prussian blue. The shown possibility to deposit stable films with regular structure in the absence of any external voltage could open new horizons for sensor science. [source]


Current-Voltage Characterisation of Monolayer-Supported Au-Nanoclusters by Scanning Tunnelling Microscopy under Ambient Conditions

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2005
Volker Jacobsen
Abstract The current-voltage characteristics of a double-tunnel junction based on a gold crystallite with a diameter of ca. 2 nm, separated from a gold surface by ca. 1 nm was investigated by scanning tunnelling microscopy. The sample architecture was built by attaching gold nanoparticles covered with 2-mercaptosuccinic acid to an atomically flat gold surface which was covered by a self-assembled monolayer (SAM) of 6-amino-1-hexanethiol. Surface plasmon and infrared spectroscopy as well as STM imaging were employed to identify suitable preparation conditions and prove the existence of the desired architecture. No reproducible steps in the current-voltage characteristics are observed on this system under ambient conditions. Nonetheless, a sound signature for tunnelling through the double-tunnel junction is established by a quantitative fit of the averaged experimental data to a theoretical model of a single-tunnel junction. Firstly, the current on the particle is strongly reduced at low absolute external voltage and secondly the current voltage characteristics are asymmetric. Since both deviations from theory are absent in reference experiments on the bare monolayer, they may serve as a robust signature for double-tunnel junctions and open the door to the investigation of single-electron tunnelling under ambient conditions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]


Anisotropic Motion of Electroactive Papers Coated with PEDOT/PSS

MACROMOLECULAR MATERIALS & ENGINEERING, Issue 7 2010
Jian Zhou
Abstract We report on an anisotropic actuation of electroactive papers with a PEDOT/PSS coating in ambient air. PEDOT/PSS-coated papers were prepared by wetting Manila papers with a concentrated PEDOT/PSS aqueous dispersion and subsequent drying. The electroactive papers displayed a contractile stress when an external voltage was applied, the magnitude and direction of the stress depending on the relative orientation of paper fibers and the loading direction of the coating. We also demonstrated that a butterfly-like reversible bending motion of the PEDOT/PSS coated paper occurred when the voltage switching between on and off. [source]


Magnetoelectric Memories,a Disruptive Techology?

CHEMPHYSCHEM, Issue 11 2009
FRS Prof., James F. Scott
Flip-flop: Recently, a diode whose diode effect can switch direction under the influence of an external voltage was reported. The polarization data of this BiFeO3 indicate that the largest photovoltaic tensor component is diagonal (see picture). This exciting development is Highlighted herein. [source]