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The present work deals with the investigation of ion-beam assisted annealing/mixing effects on compositional and structural changes in Al-Cu-Co multilayers. 800 nm thick Al₆₄Cu₂₀Co₁₆ multilayers prepared by magnetron sputtering deposition, consisting of 28 successive single-metal Al-, Cu-, and Co-nanolayers were treated by thermal annealing at 300°C, 400°C, or 500°C as well as ion irradiation by 30 MeV Cu⁵⁺ ions at fluences of 1x10¹³ to 5x10¹⁴ with an average flux of 2.38×10¹⁰ at.cm⁻²s⁻¹. The samples were characterized with SEM, EDX, XRD, and TEM including HAADF. In contrast to the original multilayer, the treated samples were found to consist of two types of alternating nanolayers. A wider coarse-grained structurally and chemically homogeneous single-phase nanolayer formed by Al₂Cu, and a narrow fine-grained two-phase nanolayer, which has a heterogeneous composite structure in which the central Co sublayer (being a residue of the original single-metal Co nanolayer) is surrounded from both sides with Al-Co sublayers, consisting of Al₉Co₂. This Co sublayer is considered to be a diffusion blocker for Al and Cu as well as hindering the movement of borders between particular nanolayers. The formation of a ternary phase in the investigated samples was not confirmed in any of the samples.

Measurement results, obtained with a CAMECA IMS 7f-auto, of an as-deposited sample and a sample after 500°C thermal treatment.

Zink oxide-based materials have a great potential to be applied in photo and electro catalysts, opto-electronic (indoor illumination, LED), etc. Attractiveness of ZnO is attributed to wide bandgap energy at room temperature (3.37 eV), high electron mobility and transfer efficiency (115-155 cm2·V-1·s-1), large exciton binding energy (60 meV), intrinsic stability, nontoxicity, environmental compatibility and also, simple and not expensive synthesis procedure. A lot of different approaches can be used to modify the bandgap (i.e. optical absorption) of ZnO materials: metal and nonmetal ion doping, hydrogenation, the incorporation of crystalline defects in the form of V and I, modification of particles morphology and surface topology, etc. In this study, eco-friendly and rapid microwave processing of a precipitate was used to produce Fe-doped ZnO nanoparticles with 5, 10, 15 and 20 at.% of Fe (Zn1-xFeyO(1-x+1.5y)). The influence of different amount of Fe substituted Zn in ZnO on the crystal structure, morphological, textural, and optical properties as well as on functionality of ZnO particles was investigated. The crystal structure and phase purity of the Zn1-xFeyO(1-x+1.5y) particles were determined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Effects of the Fe3+ amount on particles morphology and texture properties were observed with field emission scanning electron microscopy (FE–SEM), transmission electron microscopy (TEM) and nitrogen adsorption–desorption isotherm, respectively. Optical properties were studied using UV-Vis diffuse reflectance and photoluminescence spectroscopy. Functionality of ZnO particles was studied due to their photocatalytic and electrochemical activities. Photocatalytic activity was examined via decolorization of methylene blue under direct sunlight irradiation. Electrochemical behavior of the ZnO samples as anode material was evaluated by linear sw

The ion implantation technique has a number of advantages over conventional methods for the improvement of thin films that offer the various possibilities of their use in different industrial and technological fields. Herein, we present the effects of metal ion implantation on the structural and optical properties of TiN thin films. TiN films of 170 nm thickness were grown by d.c. reactive sputtering on Si (100) wafers and then irradiated at 5×1016 ions/cm2 with either Au, Ag, or Cu ions by using two different energies per each implanted metal. The results showed that as deposited TiN crystallizes in form of fcc cubic structure, with the crystallites preferentially oriented along the (111) plane. For all implanted layers the cubic crystallographic structure was preserved, but compared to as deposited TiN the crystallites were smaller and the lattice was contracted. Besides, the surface compositional analysis of as deposited sample showed the coexistence of TiN, TiO2 and TiOxNy phases and this was related to the surface oxidation of the films due to the exposure to air. After implantation, the results were almost similar for all metals, showing an increase in TiO2 contribution and the formation of pure metallic Au and Ag phases, while copper is in the Cu2+ state, which is attributed to Cu(II)-oxide and Cu(OH)2. The microstructural characteristics including defect formation, changes in the crystallite size and lattice contraction, and also growth of different metallic phases during implantations were correlated with the findings of the optical characterization of the implanted films. For as deposited film we found energy gap of 2.91 eV, which was lower than the value typical for TiN. After implantation the gap was shifted to higher energies, while at the visible part of the region, additional energy levels, at photon energies below 2.9 eV were observed. Further, all implanted films showed degraded photocatalytic activity compared to as deposited TiN, among which Cu-im