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The composition, structural features, surface morphology, roughness parameters, particle size, and magnetic features of nanostructured Fe‐Co‐Ni deposits manufactured on conducting indium tin oxide‐coated glasses at various electrolyte pH values are studied. The deposit produced at low electrolyte pH contains slightly higher Fe and Co contents but lower Ni content compared to deposits fabricated at high pH values. Further composition analysis confirms that the reduction rates of Fe2+ and Co2+ are higher than the Ni2+ reduction rate. The films consist of nano‐sized crystallites with a strong [111] preferred orientation. The results also reveal that the crystallization of the thin films is affected by the electrolyte pH. Surface analysis shows that the deposit surfaces are composed of nano‐sized particles with different diameters. The mean particle diameter and surface roughness decrease as the pH of the electrolyte decreases. The effect of the electrolyte pH on the morphology is also discussed in terms of surface skewness and kurtosis parameters. Magnetic analysis shows that the resultant deposits have in‐plane hysteresis loops with low and close SQR parameters ranging from 0.079 to 0.108. The results also reveal that the coercive field of the deposits increases from 29.4 Oe to 41.3 Oe as the electrolyte pH decreases from 4.7 to 3.2. LAY DESCRIPTION: The aim of this study is to investigate the impact of the electrolyte pH on the properties of nanostructured Fe‐Co‐Ni/ITO thin films. The chemical composition, structural features and magnetic characteristics of the samples were analyzed through EDX, XRD and VSM, respectively. SEM and AFM methods were used to characterize the surface morphology of the samples. The analysis results showed that the mean particle diameter and surface roughness of the films decreased as the pH of the electrolyte decreased. Besides, lowering the electrolyte pH led to the formation of some pinholes and cracks on the film surface. The change in the surface morphology caused by the pH of the electrolyte and its effect on the magnetic characteristics of the films are discussed in terms of the obtained results. [ABSTRACT FROM AUTHOR]

Ternary Co-Fe-Cu thin films with 78.5-92.4 at.% Co, 4.1-17.9 at.% Fe, and 3.1-3.6 at.% Cu were electroplated at ambient temperature from electrolytes with different relative Fe ion concentrations with respect to the Co ion concentration on the glass substrates coated with indium tin oxide (ITO). It was revealed that the Fe is more easily deposited than Co for all electrolyte conditions. The phase structure of the films changed from a mixture of hcp Co and fcc/hcp Co to a mixture of fcc/hcp Co and bcc Fe and the mean crystallite size diminished with increasing Fe content within the deposits. A shift in the peak position of the fcc/hcp Co phase towards lower 2θ angles with increasing Fe content within the deposits was observed and the reason for that was discussed. There was also a transition in the surface morphological structure of the films from an acicular-like type structure to a cauliower-like type structure. The changes that appeared in the surface morphology were related to phase structure, which was affected considerably by the deposit composition. [ABSTRACT FROM AUTHOR]

Microstructural features and surface morphologies of Ni-Fe thin films fabricated by the electrochemical deposition technique have been experimentally studied. Ni-Fe thin films have been deposited under different deposition potentials and FeSO4 concentrations. Energy dispersive X-ray measurements demonstrate that the Fe content decreases (increases) as the deposition potential (FeSO4 concentration) is enhanced. All of the produced films exhibit an anomalous codeposition behavior. The effects of deposition potential and FeSO4 concentrations on the degree of anomalous codeposition have been also characterized. X-ray diffraction studies reveal that the films have face-centered cubic crystallographic structures with [111] preferred crystallographic orientation regardless of the applied deposition conditions. However, the crystallization and the crystallite size of the films are affected by changing of the FeSO4 concentration and the deposition potential. The results of scanning electron microscopy analyses verify that the surface structure of the film electroplated from the electrolyte with higher FeSO4 concentration under higher deposition potential exhibits a more homogeneous and dense structure with smaller grain sizes. [ABSTRACT FROM AUTHOR]

Activated carbons were prepared from chestnut shell by phosphoric acid activation and the prepared activated carbons were used to remove lead(II) from aqueous solutions. The effects of impregnation ratio (IR) and activation temperature on activated carbon production were investigated. The produced activated carbons were characterized by N2adsorption, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. The highest surface area (1611 m2/g) and total pore volume (0.7819 cm3/g) were obtained at a carbonization temperature of 500°C with an impregnation ratio of 3/1. The resulting activated carbon was used for removal of lead(II) from aqueous solution. The effects of temperature, contact time, and adsorbent dosage were investigated. The adsorption isotherm studies were carried out and the obtained data were analyzed by the Langmuir, Freundlich, and Temkin equations. The rate of adsorption was found to conform to the pseudo-second-order kinetic model. The Langmuir isotherm equation showed better fit for all temperatures and the maximum adsorption capacities of lead(II) was obtained as 138.88 mg/g at 45°C. [ABSTRACT FROM AUTHOR]

Fe-Cu films with low and high Fe: Cu ratio have been produced from the electrolytes with different Fe ion concentrations at a constant deposition potential of -1400mV versus saturated calomel electrode (SCE) by electrodeposition technique onto indium tin oxide (ITO) coated conducting glass substrates. It was observed that the variation of Fe ion concentration in the electrolyte had a very strong influence on the compositional, surface morphological, and microstructural properties of the Fe-Cu films. An increase in the Fe ion concentration within the plating bath increased the Fe content, consequently Fe : Cu ratio within the films. The crystallographic structure analysis showed that the Fe-Cu films had a mixture of face-centered cubic (fcc) Cu and body centered cubic (bcc) α-Fe phases. The average crystallite size decreased with the Fe ion concentration. The film electrodeposited from the electrolyte with low Fe ion concentration exhibited amorphology consisting of dendritic structures. However, the filmmorphology changed from dendritic structure to cauliflower-like structure at high Fe ion concentration. The surface roughness and grain size were found to decrease significantly with increasing Fe ion concentration in the electrolyte. The significant differences observed in the microstructural and morphological properties caused by the change of Fe ion concentration in the electrolyte were ascribed to the change of Fe : Cu ratio within the films. [ABSTRACT FROM AUTHOR]