Influence of Electrodeposition Parameters on Morphology and Polymer Inclusion into Polymer/Zn Composite Coatings

In this study different type of composite coatings was obtained by electrodeposition using zinc as matrix and polymeric particles as disperse phase in zinc sulphate electrolyte. The effects of some electrodeposition parameters on the thickness and morphology of obtained composite coatings were analysed by optical microscopy, Scanning Electron Microscopy (SEM) and Energy-Dispersive X-Ray Spectroscopy (EDX) methods. Polymeric particles inclusion into zinc matrix was correlated with imposed electrodeposition parameters. It was observed that the thickness of the coatings is influenced by electrodeposition parameters. From the morphology of the coatings, it could be concluded that pure zinc has a regular surface with hexagonal crystals, while the composite coatings have fine surface structure. Also, the electrodeposition parameters influence the inclusion of the dispersed phase into metallic matrix that will influence further the different properties of the composite materials.

Testing Graphene Films Produced Through Electrochemical Exfoliation Using Sulfate Electrolytes

Graphene is one of the most commonly researched materials in nanoscience and finding a cheap and efficient method to manufacture it is highly desirable because of its incredible properties. Electrochemical exfoliation involves splitting graphite into graphene by soaking the foil in an electrolyte solution and then providing an electric current. This paper evaluates the extent to which the sulphate electrolyte used in the electrochemical exfoliation process affects the electrical resistance of films created using flakes generated from the reaction. Using the method and conducting an ANOVA test with Tukey HSD Post-Hoc test on the resultant data provides significant and varied results when concerning the electrolyte variety. This implies that changing the quality and speed of the electrolyte reaction has a definitive effect on the resistance of composite films created out of graphene flakes produced from the reaction.

APPLICATION OF ISOTHIURONIUM SALTS AS LUSTER-FORMING ADDITIVES IN COPPER PLATING

The behavior of various isothiuronium salts as brighteners in copper sulphate electrolyte has been studied.

Peculiarities of Chromium Coating in Low-Concentrated Electrolytes when Repairing Details

The physical-mechanical properties of chromium coatings from low-concentrated electrolytes with additions of organic substances were studied when comparing with similar ones from standard sulphate electrolyte. It has been established that the properties of chromium coatings from low concentrated electrolytes are superior to those of standard sulphate electrolyte. An additional advantage of low-concentrated electrolytes is less carry-over of chromium anhydrate through ventilation and wash water, which reduces the cost of cleaning them when they are discharged. However, under operating conditions, more frequent adjustment of the composition of such electrolytes is required. The electrolyte is distinguished by a good scattering over the surface of parts and covering power when restored to size on a thickness of 250-300 μm of hydraulic cylinders of agricultural and mining equipment, having a length of up to 4 m and a diameter of up to 0.5 m, an increased current output of up to 24-36 % and up to 3-4 times higher corrosion resistance, micro hardness of up to 1,300 kg / mm2, determined by the conditions of deposition relative to the standard sulfate electrolyte of chromium plating. Chromium coatings from a low-concentration electrolyte with organic additives passed the recommended tests for adhesion, tearing, wear and micro hardness according to GOST methods. Their use at the enterprises of technical service for repair of agricultural parts promises economic advantages in the field of practical application (higher deposition rate and less application time), as well as lower costs for environmental protection.

KAJIAN CYCLIC VOLTAMMETRY PENGARUH SURFAKTAN GLUCOPONE 215 CSUP DALAM ELEKTROLIT SULFAT

The preliminary study on the use of Glucopone 215 CSUP surfactant as an additive in nanoparticles preparation by means of electrochemical deposition has been investigated. Critical micelle concentration (CMC) of Glucopone 215 CSUP was firstly determined both in de-ionized water and sulphate electrolyte using ensiometer. It was found that the presence of ions of the sulphate electrolyte did not make significant change on the CMC value. Electrochemical studies were then carried out using cyclic voltammetry technique. The influence of the addition of Glucopone 215 CSUP was found beyond its CMC, namely at concentration of 1.3 wt.%. In the presence of high concentration of the surfactant, The increase of current at cathodic scan of the cyclic voltammogram was observed at more negative potential than that of without surfactant. This result should be very important in providing suitable co-electrodeposition potential for nanoparticles of Co, Ni and Cu electrodeposition assisted by glucopone 215 CSUP. Keywords: cyclic voltammetry, critical micelle concentration, Glucopone 215 CSUP, electrodepositionAbstrak Surfaktan dapat digunakan sebagai aditif yang dapat mengontrol dan memodifikasi proses pertumbuhan partikel yang dipreparasi dengan metode deposisi elektrokimia. Kajian pendahuluan terhadap pengaruh penggunaan surfaktan Glucopone 215 CSUP terhadap karakteristik elektrokimia elektrolit sulfat telah dilakukan menggunakan teknik cyclic voltammetry. Hasil pengukuran menggunakan tensiometer menunjukkan bahwa ion-ion dari elektrolit tidak menimbulkan perbedaan signifikan terhadap critical micelle concentration (CMC) surfaktan yang dikaji. Pengaruh penambahan surfaktan Glucopone 215 CSUP terhadap cyclic voltammogram teramati ketika konsentrasi surfaktan diatas nilai CMC-nya. Katodik scan dari cyclic voltammogram menunjukkan bahwa pada konsentrasi diatas surfaktan, 1,3 wt.%, titik kenaikan arus katodik bergeser ke potensial yang semakin negatif. Hasil ini memberikan informasi potensial co-electrodeposisi yang sesuai untuk Co, Ni, dan Cu yang dipreparasi dari elektrolit sulfat dengan menggunakan aditif Glucopone 215 CSUP.Keywords: cyclic voltammetry, critical micelle concentration, Glucopone 215 CSUP, elektrodeposisi

Synergetic effect of additives on the hardness and adhesion of thin electrodeposited copper films

Thin copper films were electrodeposited on a polycrystalline coldrolled copper substrate. The composition of the laboratory-made copper sulphate electrolyte was changed by the addition of various additives. The influence of chloride ion (Cl-), polyethylene glycol (PEG) and 3-mercapto-1-propane sulfonic acid (MPSA) on mechanical and adhesion properties of the electrodeposited copper films was investigated using Vickers microindentation technique. Calculations of the film hardness and adhesion were carried out using composite hardness models of Korsunsky and Chen-Gao. The hardness of the composite system is influenced by the adhesion of the copper film to the substrate. Increasing adhesion corresponds to increasing values of the calculated adhesion parameter b, named the critical reduced depth. When additives are added to a plating solution, the copper deposition mechanism is changed and fine-grained microstructure without the formation of microscopic nodules is obtained.

Electrochemical Deposition of Selenium on Copper

The present work concerns studies aiming at determination of optimal parameters of obtaining selenium coatings on a copper substrate through the cathodic reduction from sulphate and citrate solutions. The voltammetric analysis was performed in selected solutions to define electrode reactions within the examined range of potentials as well as an influence of pH on their kinetics. The range of potentials in which selenium is reduced to Se0, and then to Se2- was determined. The next stage was performing several electrolysis, where the working electrode was copper. It was to define an influence of citric acid, sodium sulphate, electrolyte pH and the electrolysis potential on the quality of the obtained coatings. The coatings were analysed with the use of X-ray spectrofluorimetry, X-ray diffraction and scanning electron microscopy.