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The electrochemical deposition of zinc/gold dendrite-free alloys was achieved from deep eutectic solvents based on a mixture of choline chloride and ethylene glycol, without using any additives. Potentiostatic electrodeposition was carried out at relatively low Zn electrodeposition overpotential at different Zn(II) concentrations. Insight into the electrochemical mechanism of the Zn electrodeposition was revealed by cyclic voltammetry (CV) and chrono- amperometry (CA). The morphology and structure of the obtained electrodeposits were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), while the elemental analysis was determined by energy dispersive spectroscopy (EDS) technique. The CV results showed that Zn electrodeposition commences with zinc underpotential deposition (UPD) and proceeds through the zinc overpotential deposition (OPD) region. The deposition potential of the Zn/Zn(II) couple shifts towards more positive value with increased Zn(II) concentration. CA analysis demonstrated that in the zinc OPD region, 3D progressive nucleation starts, followed by 3D growth of depositing zinc. Morphological analysis revealed that electrodeposition commences with the formation of compact Zn islands and proceeds through dendrite-free zinc/gold alloys formed. A formation of several intermetallics, namely cubic AuZn3 and AuZn along with metallic zinc were identified by XRD analysis.

The electrochemical deposition of zinc/gold dendrite-free alloys was achieved from deep eutectic solvents based on a mixture of choline chloride and ethylene glycol, without using any additives. Potentiostatic electrodeposition was carried out at relatively low Zn electrodeposition overpotential at different Zn(II) concentrations. Insight into the electrochemical mechanism of the Zn electrodeposition was revealed by cyclic voltammetry (CV) and chrono- amperometry (CA). The morphology and structure of the obtained electrodeposits were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), while the elemental analysis was determined by energy dispersive spectroscopy (EDS) technique. The CV results showed that Zn electrodeposition commences with zinc underpotential deposition (UPD) and proceeds through the zinc overpotential deposition (OPD) region. The deposition potential of the Zn/Zn(II) couple shifts towards more positive value with increased Zn(II) concentration. CA analysis demonstrated that in the zinc OPD region, 3D progressive nucleation starts, followed by 3D growth of depositing zinc. Morphological analysis revealed that electrodeposition commences with the formation of compact Zn islands and proceeds through dendrite-free zinc/gold alloys formed. A formation of several intermetallics, namely cubic AuZn3 and AuZn along with metallic zinc were identified by XRD analysis.

A lack of strategies for the utilization of harvest residues (HRs) has led to serious environmental problems due to an accumulation of these residues or their burning in the field. In this study, wheat and corn HRs were used as feedstock for the production of microcrystalline cellulose (MCC) by treatment with 2–8% sodium hydroxide, 10% hydrogen peroxide and further hydrolysis with 1–2 M hydrochloric acid. The changes in the FT-IR spectra and PXRD diffractograms after chemical treatment confirmed the removal of most of the lignin, hemicellulose and amorphous fraction of cellulose. A higher degree of crystallinity was observed for MCC obtained from corn HRs, which was attributed to a more efficient removal of lignin and hemicellulose by a higher sodium hydroxide concentration, which facilitates the dissolution of amorphous cellulose during acid hydrolysis. MCC obtained from HRs exhibited lower bulk density and poorer flow properties but similar or better tableting properties compared to commercial MCC (CeolusTM PH101). The lower ejection and detachment stress suggests that MCC isolated from HRs requires less lubricant compared to commercial MCC. This study showed that MCC isolated from wheat and corn HRs exhibits comparable tableting behaviour like commercial sample, further supporting this type of agricultural waste utilization.

Transition metal oxides (TMOs) have gathered increasing attention in material science due to their good electrical, mechanical, optical properties and great chemical and thermal stability. Among them, ruthenium oxide (RuO2), with its excellent catalytic performances has been the subject of numerous studies. It serves as a crucial material for electrodes in (electro)catalysis, energy storage systems, and semiconductor devices. RuO2-based catalysts have shown good potential in many important reactions such as the low-temperature dehydrogenation of small molecules (NH3, HCl, methanol), and have been utilized in industrial electrolysis for chlorine-alkali production [1,2]. There are numerous techniques to synthesize RuO2 [1]. In response to the challenges associated with RuO2 synthesis, and to customize the particle size and shape of RuO2, an electrochemical deposition from a new class of non-aqueous electrolytes, namely the deep eutectic solvents (DESs), can be a good alternative. So far, there have been recorded some attempts to electrochemically deposit ruthenium/ruthenium oxides from DES [3,4]. This study focuses on the electrochemical deposition of ruthenium oxide onto palladium working electrode from choline chloride (ChCl): urea (1:2 ratio) DES at 80 °C with 0.01M Ru(III) ions concentration. RuCl3 was added as a source of Ru ions in the working electrolyte. To determine the potential range available for Ru electrodeposition in DES, cyclic voltammetry (CV) on Pd working electrode in the electrolyte containing ChCl and urea was recorded. The potential window of electrochemical stability was between -1.2 and +0.3V vs. Pt. The electrochemical behaviour of Ru(III) in choline chloride-urea has been investigated at palladium using cyclic voltammetry (CV) and square wave voltammetry (SWV). The CV results showed only cathodic peaks without corresponding anodic counterparts, and SWV was used for further investigation in order to gain a better understanding of the Ru(III) e

Electrodeposition of copper from an eutectic mixture based on choline chloride and ethylene glycol containing copper(II) chloride salt at 50 °C was investigated. It was shown that electrochemical reduction process of Cu(II) proceeds via two steps, Cu(II) → Cu(I) and Cu(I) → Cu(0). Electrodeposits were obtained by potentiostatic electrolysis and analyzed by scanning electron microscope (SEM) and Energy-dispersive X-ray spectroscopy (EDS). SEM results showed that the electrodeposited Cu on Pd was relatively uniform and smooth, with Cu grains of approximately 1 micrometer. EDS analysis of the Pd electrode surface after Cu electrodeposition revealed that Cu is dominating in the deposit. The presence of CuPd alloy, along with metallic Cu on the Pd surface is confirmed by X-ray diffraction (XRD).

Recently, there has been an increasing interest in developing nonaqueous electrolytes which have been widely employed as an alternative media for a range of metals and metal alloys electrodepositions. A promising and new class of electrolytes among ionic liquids (Ils) are deep eutectic solvents (DESs)1 . The purpose of the copper deposition study from DESs is the application of copper coating and copper alloys in both, industry and fundamental research. In this work, the electrochemical deposition of copper onto palladium working substrate from ChCl/EG (1:2 ratio) DES electrolyte at 50°C was investigated. Additionally, the Cu(II) electroreduction process was studied by potentiodynamic measurements, cyclic voltammetry, chronoamperometry, in the electrolytes with different concentrations of Cu(II) ions ranging from 0.1 M to 0.5 M. The cyclic voltammetry results indicated that the bulk deposition of Cu(II) begins to occur at around –0.080 V vs. Cu. It was found that copper deposition onto the Pd cathode from ChCl:EG electrolyte under potentiostatic conditions is achievable. Data collected from X-ray diffraction (XRD) analysis proved that the cathodic deposits are composed of Cu and CuPd intermetallic. CuPd alloys with different Pd-Cu ratios were prepared by constant potential of –0.100 V vs. Cu from ChCl/EG containing 0.1 M and 0.5 M Cu(II). It is worth noting that the Xray data indicated that the composition of the produced Pd-Cu films could be varied by changing the concentration of Cu(II) ions in the electrolyte or changing the deposition mode.

In this investigation, samples of SrGd2O4 doped with different Yb3+ (2, 4, 6 at.%) ions and constant Ho3+ (1 at.%) and Bi3+ (2 at.%) concentrations were prepared. The sol-gel method with glycine as a fuel and citric acid as a chelator was chosen for sample preparation. All samples were heated in the furnace for 1.5 h at 500 °C and then thermally treated for 2.5 h at 1000 °C. The pure orthorhombic lattice of SrGd2O4, space group Pnma, was revealed by X-ray diffraction (XRD) (JCPDS Card No.:01-072-6387). Transmission electron microscopy (TEM) discovered agglomerated clusters of spherical particles measuring around 150 nm in size. Including Bi3+ ions into the structure influenced the morphology of the sample showing fine packing of pyramidal-shaped nanoparticles. The uniform distribution of constitutive elements in the samples was confirmed by energy dispersive spectroscopy (EDS). Up-conversion emission properties were evaluated from photoluminescent emission spectra and intensity dependence on excitation power after excitation at 976 nm. Dominant green (550 nm), red (671 nm), and infrared (758 nm) 5F4, 5S2 → 5I8, 5F5 → 5I8, 5F4, 5S2 → 5I7 transition emissions, respectively, are detected in all samples. The sample co-doped with Bi3+ showed the most intense photoluminescent emission.

A mixture of 50.0 wt% Fe, 47.0 wt% BaTiO3, and 3.0 wt% TiO2 powders is milled and then pressed and sintered. Samples sintered from ground powders have a structure consisting of plates. They consist of the crystalline phase BaFe12O19 and crystalline and amorphous phases Fe, BaTiO3, and TiO2. Samples sintered from powders ground for more than 180 min are compact and composed of BaFe12O19 crystals embedded in an amorphous matrix consisting of amorphous BaTiO3 and TiO2 phases. Magnetization of a sample ground for 220 min gradually decreases with increasing temperature up to 440°C. This decrease result from the transition of ordered domains into chaotically directed domains. Above 440°C, the thermal energy is sufficiently large to destroy ordered paramagnetic ferromagnetic and weakly ferromagnetic domains. During sample cooling in the absence of an external magnetic field, the temperature dependence of magnetization is the same as that obtained during heating in the magnetic field. However, during the sample cooling in the magnetic field, substantially higher values of magnetization are obtained. Considerably higher magnetization of the cooled sample remains even after switching off the external magnetic field. The sintered sample, previously pressed in the magnetic field, has a higher dielectric constant than the sample pressed in the absence of the magnetic field. The dielectric constant decreases with increasing frequency.

The electrochemical deposition of Zn onto Au from a choline chloride/ethylene glycol deep eutectic system containing different ZnCl2 concentrations has been investigated. The voltammetric results demonstrated that Zn electrodeposition commences in the zinc underpotential deposition (UPD) and proceeds through to the zinc overpotential deposition (OPD) region. The results of X-ray diffraction analysis revealed that the deposit prepared at a relatively low Zn overpotential of – 0.050 V vs. Zn was composed of cubic AuZn alloy. The morphology of the deposit has been characterized by means of a scanning electron microscope and displays a relatively compact and dendrite-free Zn/Au alloy deposit formed.

A novel and effective antibacterial agent based on a combination of copper nanoparticles (CuNPs) and polypyrrole (PPy) is presented. By using a straightforward in situ polymerization method in water, a copper/polypyrrole (Cu/PPy) nanocomposite with spherical CuNPs, around 25 nm in diameter, uniformly dispersed throughout a granular PPy matrix, was characterized and subjected to determination of antibacterial activity toward E. coli, and S. aureus. In this survey, the synergistic engagement of various features of CuNPs and PPy against bacteria was somewhat expected. After a 24 h interaction with S. aureus, already 2 ppm of Cu/PPy with only 9.45 wt% content of Cu is acting almost completely cidal, with 99.17 % bacterial growth inhibition, while 10 ppm has a cidal value of 99.99 % at the same time. Safe and environmentally acceptable concentrations of Cu/PPy indicate that it is convenient as an antibacterial agent for wider use.

The presented research focused on the metallization of polyester, cotton, and polyamide 6.6 fabrics using the silver conductive complex to allow electric conductivity through the fabric's surface and enhance the fabric's mechanical properties. The method used for the metallization of studied fabrics does not require the use of expensive toxic chemicals or electricity, making the process more economically acceptable. The signal attenuation was measured in frequency ranges of 1–4 and 5–12 GHz. After five cycles of metallization, the polyester fabric has higher EMI effectiveness, in a lower range was 45.44 and 57.25 dB. X-ray powder diffractometry (XRD) and infrared spectroscopy with Fourier transform infrared spectrophotometry (FT-IR) characterize the modified tissues. Scanning electron microscopy coupled with energy-dispersion spectroscopy (SEM-EDS) was used to determine layers' morphology and elemental composition. Also, the water and air permeability of modified textiles was determined.