M. V. Zdorovets

Influence of electrodeposition parameters on structural and morphological features of Ni nanotubes

Nickel nanotubes have been formed in pores of ion-track membranes using electrochemical deposition. Morphologic and structural features of these nanostructures have been comprehensively studied. The evolution of the nanotubes wall thickness and parameters of their crystalline structure by variations of the synthesis voltage and temperature has been determined. On the base of these data the nanotubes growth mechanism has been estimated.

Electrochemically deposited copper nanotubes

Copper nanotubes are electrochemically synthesized using ion-track polyethylene terephthalate templates. The structure and morphology of the nanotubes constructed under different synthesis conditions are studied with the assistance of scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction analysis, and the manometric gas-permeability method. The dependence of structural features on the electrodeposition potential is established.

Comprehensive Study of Ni Nanotubes for Bioapplications: From Synthesis to Payloads Attaching

Due to the Ni nanotubes’ shape anisotropy, low specific density, large specific surface, and uniform magnetic field, they have been offered as carriers for targeted delivery of drug or protein and the process of their formation from synthesis stage to the stage of surface modification and protein attaching has been demonstrated. Some steps to hasten their biomedical application have been applied. First, to have full control over the carrier dimensions and structure parameters, electrodeposition method in pores of polyethylene terephthalate template has been applied. Second, to understand the scope of Ni nanostructures application, their degradation in media with different acidity has been studied. Third, to improve the biocompatibility and to make payloads attachment possible, nanotubes surface modification with organosilicon compound has been carried out. At last, the scheme of protein attaching to the nanostructure surface has been developed and the binding process was demonstrated as an example of the bovine serum albumin.

Evaluation of the catalytic activity of the composite track-etched membranes for p-nitrophenol reduction reaction

The catalytic properties of composite materials produced by electroless deposition of gold and silver into nanosized channels of polyethylene terephthalate (PET) track-etched membranes (TeMs) have been addressed. Applying the activation solution with sodium potassium tartrate as a reducing agent makes it possible to prepare PET/Ag/Au composites. The dimension (wall thickness), the structure, and the composition of the deposited metallic nanotubes have been determined by scanning electron microscopy and energy dispersive X-ray diffraction analysis. Liquid-phase reduction of p-nitrophenol as a model system has been used to examine the catalytic activity of the composites, and catalytic ability has been studied as a function of the nanotube wall thickness. It has been found that the mixed PET/Ag/Au composite can mediate the reaction to the most complete extent at the highest rate, with the catalytic activity remaining quite high for five consecutive test cycles.

Structure and physical properties of iron nanotubes obtained by template synthesis

Iron nanotubes with an aspect ratio of approximately 100 are synthesized by electrochemical deposition using polyethylene terephthalate templates. The structural and morphological features of the nanotubes are studied in detail by scanning electron microscopy, energy dispersive analysis, transmission electron microscopy, electron diffraction, X-ray diffraction analysis, and gas permeability. The main magnetic parameters and their dependence on temperature are determined by vibration magnetometry and Mössbauer spectroscopy.

The effect of oxidation pretreatment of polymer template on the formation and catalytic activity of Au/PET membrane composites

This paper reports on the synthesis and structure elucidation of the track-etched membranes with embedded gold nanotubes (prepared in etched-only and COOH-enriched PET track-etched membranes) as well as comparative testing of the catalytic activity of prepared composites. The carboxylic group functionality was enriched by successive oxidation by hydrogen peroxide and UV. “As-prepared” and oxidized membrane composites were examined for catalytic activity using reduction of 4-nitrophenol (4-NP) by NaBH4. The catalytic activity of Au/PET-Ox composite was found to be 23% more effective than Au/PET-Etch composites. Nanocomposites were also investigated by XRD, XPS and SEM techniques.Graphical Abstract

The behavior of Ni nanotubes under the influence of environments with different acidities

The results of research on the behavior of Ni nanotubes under the influence of environments with different pH values are presented. The influence of exposure time on morphology and composition under specific test conditions was investigated, and a detailed study of the nanotube crystal structure parameters vs. time was carried out. Based on the obtained results, a mechanism for the degradation of Ni nanotubes under different conditions was suggested.

Asymmetrical track-etched membranes prepared by double-sided irradiation on the DC-60 cyclotron

Asymmetric track-etched membranes based on polyethylene terephthalate have been prepared using two-sided irradiation on the heavy-ion accelerator DC-60. A process for cyclotron adjustment to bombardment of a polymer material has been described. A procedure for preparing asymmetric track-etched membranes with different pore lengths and sizes has been specified. The strength characteristics of the resulting membrane have been evaluated. It has been shown that the membrane can be used in processes in which the driving force is hydraulic or osmotic pressure.

Effect of thermal annealing on the structural and conducting properties of zinc nanotubes synthesized in the matrix of track-etched membranes

Results of studies of the effect of thermal annealing on the structural and conducting properties of ordered arrays of zinc nanotubes prepared by electrochemical deposition in track-etched membranes based on polyethylene terephthalate (PET) have been described. The dimensions, chemical composition, and crystal structure of the synthesized samples have been integrally analyzed using scanning electron microscopy, X-ray diffraction, and energy dispersive analysis. It has been shown that the thermal annealing of zinc-based nanotubes makes it possible to control the formation of an oxide phase in the nanostructures. The presence of the ZnO oxide phase in an amount of no more than 10 wt % leads to a decrease in the resistivity and an increase in the conductivity. In addition, by changing the crystal structure of Zn nanotubes by thermal annealing, it is possible to prepare ordered arrays of n-type semiconductors with considerable prospects of widespread use in nanoelectronics and nanooptics.

Structural and Conductive Characteristics of Fe/Co Nanotubes

The properties of Fe/Co nanotubes, which were fabricated by the method of electrochemical template synthesis, are studied. It is shown that the atomic ratio between the metals in the nanotubes shifts in the direction of cobalt with increasing potential difference during their synthesis; the geometric parameters of nanotubes, in particular, the wall thickness, also vary. Using the X-ray diffraction analysis, it was found that an increase in the concentration of cobalt in the crystal structure of nanotubes leads to a decrease in the interplanar distance and an increase in the conductivity.