A new approach for electrodeposition of poly (3, 4-ethylenedioxythiophene)/polyaniline (PEDOT/PANI) copolymer

In this study, poly (3, 4-ethylenedioxythiophene) (PEDOT) and polyaniline (PANI) based copolymer was synthesized by electrochemical oxidative polymerization using chronoamperometry technique. A new approach was used to perform the copolymerization process. The copolymer film was prepared at a potential obtained from the intercept point in the LSV of the both monomers. The electrodeposition was performed in solution containing 10mM of concentrations of each monomer and 0.1 M lithium perchlorate (LiClO4). The resulting conducting polymer films were characterized using scanning electron microscope (SEM), Raman spectroscopy and Fourier transform infrared (FTIR) to study the surface morphology, chemical properties and the presence of the functional groups of the conducting polymer films. The FTIR and Raman spectra proved the successful formation of the conductive polymers and copolymer onto the ITO glass. The electrochemical properties of the resultant polymer films were further analyzed using the cyclic voltammetry and electrical impedance spectroscopy

Fabrication of highly ordered TiO2 Nanotubes from Fluoride containing Aqueous Electrolyte by Anodic Oxidation and their Photoelectrochemical response.

The fabrication of TiO2 nanotubes (TNT) was carried out by electrochemical anodization of Ti in aqueous electrolyte containing NH4F. The effect of electrolyte pH, applied voltage, fluoride concentration and anodization duration on the formation of TNT was investigated. It was observed that self-organized TNT can be formed by adjusting the electrolyte to pH 2-4 whereby applied voltage of 10-20 V can be performed to produce highly ordered, well-organized TNT. At 20 V, TNT can be fabricated in the concentration range of 0.07 M to 0.20 M NH4F. Higher fluoride concentration leads to etching of Ti surface and reveals the Ti grain boundaries. The prepared TNT films also show an increase in depth and in size with time and the growth of TNT films reach a steady state after 120 minutes. The morphology and geometrical aspect of the TNT would be an important factor influencing the photoelectrochemical response, with higher photocurrent response is generally associated with thicker layer of TNT. Consequently, one can tailor the resulting TNT to desired surface morphologies by simply manipulating the electrochemical parameters for wide applications such as solar energy conversion and photoelectrocatalysis

Low-temperature synthesis of ZnO by wet chemical method

Zinc oxide (ZnO) wire was synthesized by hydrothermal method at 70° C by using Zn acetate dihydrate and ammonium hydroxide as the starting material. The sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron disperse X-ray (EDX), electro diffraction (ED) and transmission electron microscopy (TEM). The XRD result confirmed the formation of ZnO with wurtzite structure. The ED reveals that ZnO wire is single crystal and grows up along [001] direction. Influence of temperature on crystal growth was evaluated. Results shown that increase in temperature shorten the length of wire

Cathodic electrodeposition of SnS thin films from aqueous solution

SnS thin films were prepared by cathodic electrodeposition on ITO/glass and Ti substrates from a solution containing SnCl2 and thiosulphate ions. Cyclic voltammetry experiments were performed to elucidate the electrodic processes occurred when potentials were applied and to determine the optimum potential for electrodeposition. The photoactivity of the deposited films and their conduction types were evaluated using the photoelectrochemical technique. The bandgap energy and type of optical transitions were determined from optical absorbance data. Structural and compositional analysis were accomplished using X-ray diffractometry, electron dispersive analysis of X-ray, and X-ray photoelectron spectroscopy. The morphology of the films were examined using scanning electron microscopy

Electrochemical reduction of potassium ferricyanide mediated by magnesium diboride modified carbon electrode.

Use of a glassy carbon (GC) modified by adhered microparticles of MgB2 mediates the reduction process of Fe(III)(CN)63- during cyclic voltammetry. Peak potential was observed to shift slightly to less negative value by about 50 mV and current is significantly enhanced by about two folds. The sensitivity under conditions of cyclic voltammetry is significantly dependent on pH, electrolyte and scan rate. The result of scanning electron micrograph of MgB2 obtained before and after electrolysis show the size increased slightly to the size ranging from 2 - 5.5 µm attributing to the hydration effect and/or incorporation of some ionic species into the crystal lattices of MgB2. Interestingly, redox reaction of Fe(III) solution using modified GC electrode remain constant even after 15cycling. It is therefore evident that the MgB2 modified GC electrode posseses some degree of stability. Potential use of MgB2 as a useful electrode material is therefore clearly evident

Kitar voltametri pengelektroenapan timah dan timah sulfida di atas titanium dalam larutan akueous

Cyclic voltammetry showed that Sn can be deposited on Ti electrode from aqueous solution containing SnCl2 at overpotential of at least 0.06 V. SnS can also be electrodeposited from the mixture of aqueous solution of SnCl2 and thiosulphate at potential greater than -0.5V vs SCE. The existence of small stripping peak marked Sn element content in the deposit. The stoichiometry of the deposit may be approached by controlling the deposition potential and solution composition

A comparison of sorption and photodegradation study in the removal of basic and reactive dyes

A comparative study on the effectiveness of using ethylenediamine modified rice hull (MRH) and titanium dioxide (TiO2) under ultraviolet irradiation to remove both basic and reactive dyes from aqueous solutions was carried out. The sorption characteristics of Basic Blue 3 (BB3) and Reactive Orange 16 (RO 16) by MRH were studied under various experimental conditions. Studies on the sorption of both dyes showed that sorption was pH and concentration dependent. Langmuir equation was employed to model the sorption behavior of MRH. Maximum sorption capacities calculated from the Langmuir model are 3.29 and 24.88 mg/g for BB3 and RO16, respectively. The effect of initial concentrations as well as light source was carried out in the photodegradation of BB3 and RO16. BB3 with concentration of 50 mg/l was totally degraded after 6 hours of contact with TiO2 under UV illumination whereas RO 16 at the same concentration was completely decolorized at illumination time of 5 hours. The decolorizing efficiency decreased with increasing dye concentration and a higher efficiency was obtained under solar light illumination