Interfacial Design of Silicon/Polypyrrole Junctions

1999 ◽  
Vol 598 ◽  
Author(s):  
Namyong Y. Kim ◽  
Inge E. Vermeir ◽  
Paul E. Laibinis
Keyword(s):  
Electrochemical Polymerization ◽  
Silicon Surfaces ◽  
Polymerization Process ◽  
Phase Reaction ◽  
Chemically Modified ◽  
Polypyrrole Films ◽  
Molecular Film ◽  
Electrochemical Control ◽  
Current Densities ◽  
Organolithium Reagent

ABSTRACTHydrogen-terminated silicon surfaces exposing a molecular film of covalently grafted pyrrole units were formed by a solution-phase reaction using the organolithium reagent 5-(N-pyrrolyl)pentyllithium. Electrochemical polymerization of pyrrole onto native hydrogen-terminated silicon surfaces and these chemically modified supports produced silicon/polypyrrole junctions that showed diode-like characteristics, with those formed on the latter substrate exhibiting higher current densities and better ideality factors. The presence of the grafted pyrrole films on silicon provided a better electrochemical control over the polymerization process and yielded smoother polypyrrole films than on the native hydrogen-terminated silicon supports. Impedance measurements revealed that the electrical improvements to the silicon/polypyrrole junctions were a consequence of incorporating sites on the silicon surface for direct contact between the conducting polymer and the semiconductor, as the barrier height of the junction appeared to be unaffected by the chemical modification.

Monitoring the polymerization process of polypyrrole films by thermogravimetric and X-ray analysis

2010 ◽  
Vol 102 (2) ◽  
pp. 695-701 ◽  
Author(s):  
J. López ◽  
F. Parres ◽  
I. Rico ◽  
J. Molina ◽  
J. Bonastre ◽  
...  
Keyword(s):  
Polymerization Process ◽  
X Ray ◽  
Polypyrrole Films

Electrochemical polymerization process and excellent electrochromic properties of ferrocene-functionalized polytriphenylamine derivative

2019 ◽  
Vol 163 ◽  
pp. 433-440 ◽  
Author(s):  
Xiaojing Lv ◽  
Conghui Huang ◽  
Alexey Tameev ◽  
Liang Qian ◽  
Rui Zhu ◽  
...  
Keyword(s):  
Electrochemical Polymerization ◽  
Polymerization Process ◽  
Electrochromic Properties

Polyaniline: Influence of Polymerization Current Density

1994 ◽  
Vol 369 ◽  
Author(s):  
Steen Skaarup ◽  
L.M.W.K. Gunaratne ◽  
Keld West ◽  
Birgit Zachau-Christiansen
Keyword(s):  
Cyclic Voltammetry ◽  
Current Density ◽  
High Current Density ◽  
Electrochemical Polymerization ◽  
Regular Structure ◽  
Spectral Lines ◽  
Complex Nature ◽  
Cyclic Voltammograms ◽  
Layer By Layer ◽  
Current Densities

AbstractPolyaniline has been synthesized in propylene carbonate by galvanostatic electrochemical polymerization at current densities between 16 and 1000 μA/cm2. Earlier results for polypyrrole have shown that low and high current density films have different properties: The films synthesized at low current density have a higher conjugation length and a more regular structure. The corresponding effect in PANI has been investigated by cyclic voltammetry and UV/visible spectroscopy. Simultaneous measurement of cyclic voltammograms and the absorbtion of selected spectral lines is used because of the complex nature of the PANI system which involves several redox systems as well as forms differing in the degree of protonation and morphology.The main result is that the method of galvanostatic synthesis at low current densities (-16 μA/cm2) produces polyaniline polymers of different, more conjugated and more regular structure than those prepared at higher current densities. The standard method of in situ layer-by-layer polymerization of conducting polymers during cyclic voltammetry often results in uncontrolled and unmeasured current densities of 0.5-2 mA/cm2 which produces a film that probably has a less regular structure containing more deviations from ideality.

Actuative Properties of CP Actuator Consisting of Polypyrrole Film and Solid Polymer Electrolyte

2007 ◽  
Vol 336-338 ◽  
pp. 341-344 ◽  
Author(s):  
Hye Ran Kang ◽  
Hae Do Jung ◽  
Jang Oo Lee ◽  
Nam Ju Jo
Keyword(s):  
Polymer Electrolyte ◽  
Conducting Polymer ◽  
Electrolyte Solution ◽  
Solid Polymer Electrolyte ◽  
Oxidation Process ◽  
Electrochemical Polymerization ◽  
Solid Polymer ◽  
Polypyrrole Films ◽  
Polypyrrole Film

Conducting polymer (CP) actuators undergo volumetric changes due to the movement of dopant ions into the film during the electrical oxidation process. However, it may be an impediment for practical use of polypyrrole actuator that polypyrrole usually requires electrolyte solution for actuation. To solve this problem, solid polymer electrolyte(SPE) was introduced in CP actuator instead of electrolyte solution. And PPy/SPE/PPy electroactive tri-layer actuator was prepared by the electrochemical polymerization of pyrrole and the actuation characteristics were studied. An all-solid actuator, consisting of two polypyrrole films and a solid polymer electrolyte based on polyurethane, clearly showed a reversible displacement in an atmosphere when a voltage was applied.

Highly Improved Electrooxidation of Captopril on Copper Hexacyanoferrate/Ordered Mesoporous Carbon-Modified Glassy Carbon Electrode

2014 ◽  
Vol 67 (6) ◽  
pp. 851 ◽  
Author(s):  
Shengjun Lu ◽  
Pan Lu ◽  
Cheng Li ◽  
Caihong Wang ◽  
Jie Yu
Keyword(s):  
Glassy Carbon Electrode ◽  
Glassy Carbon ◽  
Mesoporous Carbon ◽  
Electrochemical Polymerization ◽  
Ordered Mesoporous Carbon ◽  
Polymerization Process ◽  
Carbon Electrode ◽  
Modified Glassy Carbon Electrode ◽  
Copper Hexacyanoferrate ◽  
Ordered Mesoporous

Using an electrochemical polymerization process, a copper hexacyanoferrate/ordered mesoporous carbon-modified glassy carbon electrode (CuHCF/OMC/GCE) was prepared. The performance of CuHCF/OMC was compared with that of CuHCF and the properties of the new material were improved. A sensor for sensitive detection of captopril was developed based on CuHCF/OMC-modified glassy carbon electrode. The composition and morphology of the as-prepared CuHCF/OMC products were characterized by energy-dispersive X-ray spectroscopy and scanning electron microscopy. The electrochemical behaviour and electrocatalytic performance of the CuHCF/OMC-modified glassy carbon electrode towards the oxidation of captopril were evaluated by cyclic voltammetry. Results showed that the CuHCF/OMC-modified electrode exhibits two well-defined redox peaks. The linear range for the detection of captopril was from 1.0 × 10–5 to 2.7 × 10–3 M, with a correlation coefficient of 0.999, and the detection limit was 1.2 × 10–6 M based on a signal-to-noise ratio of 3.

The Research of Modified-Soy-Protein – Acrylate Hybrid Emulsion

2010 ◽  
Vol 113-116 ◽  
pp. 1818-1823 ◽  
Author(s):  
Shi Cheng Zhang ◽  
Li Na Dong ◽  
Jiu Yin Pang ◽  
Chuan Sun
Keyword(s):  
Soy Protein ◽  
Water Resistance ◽  
Sem Analysis ◽  
Solid Content ◽  
Polymerization Process ◽  
Particle Structure ◽  
Excellent Performance ◽  
Chemical Methods ◽  
Adhesion Properties ◽  
Chemically Modified

The main purpose of determining excellent performance of the system of emulsion through the chemical methods (MATS surface treatment)on soy-protein chemically modified, add a small amount of coupling agent as a horizontal cross-linker, and further enhance its water resistance and the strength of cement, in order to higher requirements. Research will be used description the solid content etc. of polymerization process used measure weight、viscosity etc., and analysis of particle structure and shape by TEM, SEM, analysis the surface properties of particles by FTIR, and ascertain by measuring adhesion properties of different emulsion on the same substrate by strength capability.

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