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The giant magnetoresistance (GMR) was investigated for electrodeposited Co/Cu multilayers. In order to better understand the formation of individual layers and their influence on GMR, multilayers produced by two different deposition strategies were compared. One series of Co(2 nm)/Cu(t Cu ) multilayers with t Cu ranging from 0.5 nm to 6 nm was produced with the conventional two-pulse plating by using a galvanostatic/potentiostatic (G/P) pulse combination for the magnetic/non-magnetic layer deposition, respectively, whereby the Cu layer deposition was carried out at the electrochemically optimized potential. Another Co(2 nm)/Cu(t Cu ) multilayer series with the same t Cu range was prepared with the help of a G/P/G pulse combination. In this latter case, first a bilayer of Co(2 nm)/Cu(6 nm) was deposited in each cycle as in the G/P mode after which a third G pulse was applied with a small anodic current to dissolve part of the 6 nm thick Cu layer in order to ensure the targeted t Cu value. The comparison of the two series revealed that the G/P/G pulse combination yields multilayers for which GMR can be obtained even at such low nominal Cu layer thicknesses where G/P multilayers already exhibit bulk-like anisotropic magnetoresistance only. Surface roughness measurements by atomic force microscopy revealed that the two kinds of pulse combination yield different surface roughness values which correlate with the structural quality of the multilayers as indicated by the absence or presence of multilayer satellite reflections in the X-ray diffraction patterns. A separation of the superparamagnetic (SPM) contribution from the total observed GMR provided useful hints at the understanding of differences in layer formation between samples prepared with the two kinds of pulse combination. The results of multilayer chemical analysis revealed that mainly an increased Cu content of the magnetic layer is responsible for the onset of SPM regions in the form of Co segregations in the G/P/G multilayers with small Cu layer thicknesses. Magnetization measurements provided coercive force and remanence data which gave further support for the above interpretation of the GMR data. The giant magnetoresistance (GMR) effect in electrodeposited (ED) multilayer films was extensively studied in the last two decades.

In the present work, the pulse electrodeposition of tin from sulphate bath containing SnSO 4 , H 2 SO 4 , phenol sulphonic acid, gelatin and ß-napthol has been studied. The influences of pulsed current, duty cycle on the thickness, hardness and current efficiency of the tin deposit were studied. Electrochemical corrosion studies of the deposited tin on mild steel were conducted by potentiodynamic polarisation and electrochemical impedance spectroscopy. Cyclic voltammetry studies using potential sweep of 10 mV s 21 provide information about the potential ranges for tin deposition and stripping. The tin deposit on a brass substrate has been investigated using XRD, SEM and AFM. The XRD analysis revealed that the tin plated is Sn(200) and crystalline. The morphology of tin deposit is a typical fine grained and granular structure as seen from SEM and AFM.

Cu-Ni alloy coatings on copper substrate by the brush-plating process have been investigated using XRD and AFM. The X-Ray diffraction analysis revealed that the brush-plated Cu-Ni alloy was heterogeneous and composed of cubic Cu 3.8 Ni phases. Uniform surface coverage of the substrate by granular morphology was observed from AFM. The corrosion protection performance of the brush-plated Cu-Ni alloy on copper substrate has been assessed using electrochemical corrosion tests. These results indicated a high charge transfer and low I corr for the alloy system compared with copper deposits and the copper substrate.

Zinc–tin–vanadium oxide (ZTV) nanocomposite room temperature ethanol sensor (98.96% for 300 ppm) with fast adsorption (32 s) and desorption (6 s) rate is reported for first time and the mechanism is elucidated based on its structure and morphology.

Electrodeposition of aluminium on the copper substrate using two different chloroaluminate ionic liquid electrolytes such as AlCl 3 /1-Butyl-3-methylimidazolium chloride electrolyte (AlCl 3 -BMIC) and AlCl 3 /1-Ethyl-3-methylimidazolium chloride electrolyte (AlCl 3 -EMIC) were studied. Cyclic voltammetry studies reveal the aluminium deposition process follows two steps mechanism in AlCl 3 -EMIC electrolytes and in AlCl 3 -BMIC electrolytes, it follows single-step mechanism. The AlCl 3 -EMIC electrolytes permit wide deposition current density window than the AlCl 3 -BMIC electrolytes for aluminium deposition with good properties. The aluminium deposits obtained from AlCl3-EMIC electrolyte have better surface properties than the deposits obtained from AlCl 3 -BMIC electrolyte. Detailed comparative studies of deposits obtained from these two electrolytes with respect to deposition mechanism, deposition efficiency and deposition current density window were done. The deposit properties such as surface morphology, microstructure and crystal structures were also compared. From this study, we observed the AlCl 3 -EMIC electrolyte gives good quality deposits than AlCl 3 -BMIC electrolyte.

Cu-Ni alloys were electrodeposited by the brush plating technique from sulphate/citrate electrolyte at various pH values. The effects of pH on composition and surface morphological properties of alloys were investigated by X-ray fluorescence and atomic force microscopy. The Cu content increased in the composition of Cu-Ni alloy at electrolyte pH 2. The deposition mechanisms of Cu, Ni and Cu-Ni were investigated by cyclic voltammetry. The lower electrolyte pH leads to the higher reduction current density. The corrosion behaviours of the deposits at different pH values were investigated by Tafel analysis and electrochemical impedance spectroscopy. The corrosion studies indicate that the Cu-Ni alloy exhibits better corrosion resistance at higher pH values than at lower pH values. The surface roughness decreases with increasing solution pH and this observation was confirmed by atomic force microscopy measurements.

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