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In this work, the specific role of the addition of graphene oxide (GO) to state-of-the-art nickel–iron (NiFe) and cobalt–nickel–iron (CoNiFe) mixed oxides/hydroxides towards the oxygen evolution reaction (OER) is investigated. Morphology, structure, and OER catalytic activity of the catalysts with and without GO were studied. The catalysts were fabricated via a two-step electrodeposition. The first step included the deposition of GO flakes, which, in the second step, were reduced during the simultaneous deposition of NiFe or CoNiFe. As a result, NiFe-GO and CoNiFe-GO were fabricated without any additives directly on the nickel foam substrate. A significant improvement of the OER activity was observed after combining NiFe with GO (OER overpotential η(10 mA·cm−2): 210 mV) compared to NiFe (η: 235 mV) and GO (η: 320 mV) alone. A different OER activity was observed for CoNiFe-GO. Here, the overall catalytic activity (η: 230 mV) increased compared to GO alone. However, it was reduced in comparison to CoNiFe (η: 224 mV). The latter was associated with the change in the morphology and structure of the catalysts. Further OER studies showed that each of the catalysts specifically influenced the process. The improvement in the OER by NiFe-GO results mainly from the structure of NiFe and the electroactive surface area of GO.

This research paper addresses the hypothesis that powdered milk may contain amyloid fibrils. Amyloids are fibrillar aggregates of proteins. Up to this time, research on the presence of amyloids in food products are scarce. To check the hypothesis we performed thioflavin T fluorescence assay, X-ray powder diffraction, atomic force microscopy and fluorescence microscopy imaging. Our preliminary results show that commercially available milks contain fibrils that have features characteristic to amyloids. The obtained results can be interpreted in two opposite ways. The presence of amyloids could be considered as a hazard due to the fact that food products may induce amyloid related diseases. On the other hand, the presence of amyloids in traditionally consumed foodstuffs could serve as proof that fibrils of food proteins do not pose a threat for consumers.

This article presents electrolytic deposition of thin Rare Earth (RE) coatings on Crofer 22 APU stainless steel substrates for high temperature applications, such as interconnects in solid oxide cell stacks. The deposition of coatings based on yttrium-, gadolinium-, lanthanum-, and cerium nitrates is discussed. The high temperature corrosion properties of surface-modified steels were examined using thermogravimetry and electrical resistivity measurements. Coatings and oxide microstructures were examined by XRD and SEM of surfaces and cross-sections. The results showed that the use of the RE element oxide layers reduced the growth of oxide scale, as evidenced by lower weight gain. The layers based on Y- and Gd-oxides showed the best corrosion protection properties. The electrical measurements showed that the surface-modified samples had lower resistance than the uncoated sample.

In the chemical industry, 1,4-diethylene dioxide, commonly called dioxane, is widely used as a solvent as well as a stabilizing agent for chlorinated solvents. Due to its high miscibility, dioxane is a ubiquitous water contaminant. This study investigates the effectiveness of catalyst- and ultrasound (US)-assisted persulfate (PS) activation with regard to degrading dioxane. As a first step, a composite catalyst was prepared using zeolite. A sonochemical dispersion and reduction method was used to dope zeolite with iron nanoparticles (FeNP/Z). In the subsequent study, the reaction kinetics of dioxane degradation following the single-stage and two-stage addition of PS was examined in the presence of a catalyst. Using GC-MS analysis, intermediate compounds formed from dioxane degradation were identified, and plausible reaction pathways were described. Upon 120 min of sonication in the presence of a catalyst with a two-stage injection of PS, 95% 100 mg/L dioxane was degraded. Finally, the estimated cost of treatment is also reported in this study. Sonolytically activated PS combined with a FeNP/Z catalyst synergizes the remediation of biorefractory micropollutants such as dioxane.

In this study, anatase samples enclosed by the majority of three different crystal facets {0 0 1}, {1 0 0}, and {1 0 1} were successfully synthesized. These materials were further studied toward photocatalytic degradation of phenol and toluene as model organic pollutants in water and gas phases. The obtained results were analyzed concerning their surface structure, reaction type, and surface development. Moreover, the regression model was created to find the correlation between the possible predictors and the photodegradation rate constants (k). From the studied factors, the trapping energy of charge carriers at the surface was found to be the most significant one, exponentially affecting the observed k. This resulted in the overall per-surface activity between the samples being in the order {1 0 1} > {1 0 0} > {0 0 1}. Further introduction of the surface energy (Esurf) to the regression model and the number of possible trapping centers per number of pollutant’s molecules (ntrap·n–1) improved the model accuracy, simultaneously showing the dependence on the reaction type. In the case of phenol photocatalytic degradation, the best accuracy was observed for the model including Esurf ·(ntrap·n–1)1/2 relation, while for the toluene degradation, it included Esurf2 and the S·n–1 ratio, where S is the simple surface area. Concerning different surface features which influence photocatalytic performance and are commonly discussed in the literature, the results presented in this study suggest that trapping is of particular importance. published

Gold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between the two metals. Increasing interest in their internal structure, such as the composition or distribution of the Au and Cu as well as the size and shape of the nanoparticles, have developed to define their physicochemical properties.In this work, we present the influence of thermal treatment in temperature ranges from 100 to 600 °C on the formation process of bimetallic AuCu structures and their properties. AuCu materials were placed on nanostructured titanium foil substrates that were fabricated using electrochemical anodisation and chemical etching. Thin layers of AuCu mixture, as well as Au and Cu, were sputtered on the obtained Ti nanodimples. The materials were then annealed in a rapid thermal annealing furnace in an air atmosphere. Thermal treatment strongly affected the morphology and optical properties of the fabricated materials. AuCu NPs formed at 400 °C in titanium dimples. The material exhibits absorption of visible light in the range from c.a. 400 to 700 nm. The characterisation of the chemical nature of the samples was determined using X-ray photoelectron spectroscopy. In addition, X-ray diffraction and Raman spectroscopy defined composition and crystallinity. Based on photoelectrochemical studies carried out with the use of linear voltammetry in 0.1 M NaOH, it is possible to distinguish two types of interactions of light with the materials such as photogenerated charge accumulation and electron–hole pair separation. A 10AuCu electrode annealed at 300 °C achieved the highest current registered under illumination at − 0.17 V vs. Ag/AgCl/0.1 M KCl. The value was 11 times higher than for a non-annealed structure.

This work presents pulsed UV laser treatment (355 nm, 2 Hz) of TiO2 nanotubes decorated with chromium oxides. The modification was performed in a system equipped with a beam homogenizer, and during the irradiation, the samples were mounted onto the moving motorized table. In such a system, both precisely selected areas and any large area of the sample can be modified. Photoelectrochemical tests revealed photoresponse of laser-treated samples up to 1.37- and 18-fold under the illumination with ultraviolet-visible and visible light, respectively, in comparison to bare titania. Optimal beam energy fluence regarding sample photoresponse has been established. Scanning electron microscopy images, X-ray diffraction patterns, along with Raman and X-ray photoelectron spectra, suggest that the enhanced photoresponse results from changes solely induced in the layer of chromium oxides. It is believed that the results of the present work will contribute to a wider interest in laser modification of semiconductors exhibiting improved photoelectrochemical activity.

Titanium oxyfluoride (TiOF2) is a metastable product that can be obtained in a fluorine-rich environment. This material can also be a valuable precursor in the synthesis of titanium(IV) oxide (TiO2). However, the effect of TiOF2 morphology on the physicochemical properties of TiO2 has not been studied so far. In this work, single-phase TiOF2 was prepared by a solvothermal method. The as-synthesized samples exhibited a variety of morphologies, including different shapes and crystallite sizes. These materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDS), surface area measurements, thermal gravimetric analysis (TGA) and UV–vis diffuse reflectance spectroscopy (DR/UV–vis). Furthermore, TiOF2 samples were used as precursors in the synthesis of fluorine-doped titanium(IV) oxide and applied in photocatalytic phenol degradation under UV-vis light. The experiments showed that the crystallite size of the precursor, as well as the number of fluoride ions used in the synthesis, were the predominant factors that affected the photocatalytic activity of the final photocatalyst.

This analysis was carried out to determine the elemental composition of selected items of metalwork. Analysis was performed using SEM-EDS, which allowed the concentration of major elements to be determined. Fifty-seven artefacts were selected for analysis, most of them made of copper alloys. The analysed finds fall into four raw material categories. The first consists of iron artefacts or items that are iron-based. The second comprises objects made of copper alloys. The third is represented by those made of silver alloys. Tin-lead artefacts make up the last group. The vast majority of the analysed items are made of copper alloys There is a clear prevalence of brass objects, with many fewer bronze ones. It is worth noting the surprising purity of both the brass and bronze alloys. These results are unexpected, given that it is thought that almost all alloy artefacts were made were made from recycled metals.

In the present study, alkaline-earth metal scheelite-type compounds ABO4 (A = Ca, Sr, Ba, B = Mo, W) synthesized by a hydrothermal method were systematically studied. The as-obtained photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area analysis (BET), UV–Vis diffuse reflectance spectroscopy (DR/UV-Vis), photoluminescence, and thermoluminescence (TL) spectroscopy together with charge carrier’s lifetime measurements, electron paramagnetic resonance spectroscopy (EPR) and electrochemical impedance spectroscopy (EIS). The photocatalytic activity was studied in the reaction of phenol degradation under simulated solar light. The obtained tungstates and molybdates revealed excellent photocatalytic activity despite the low surface area and wide-bandgap typical for insulators. The mechanism of phenol degradation proceeded through hydroquinone and catechol formation in the presence of hydroxyl and superoxide radicals. The presence of electron traps allowed to absorb light with lower energy than resulting from the absorption edge. BaWO4 and SrWO4, with the most extended average carrier lifetime, were the most efficient photocatalysts from obtained series. In general, molybdates exhibited lower photocatalytic activity towards phenol degradation due to deeper trap states and lower average charge carriers' lifetimes than tungstates. Additionally, electrochemical studies emerged that molybdates exhibit more insulating behavior than tungstates. Overall results showed that wide-bandgap semiconductors, mainly tungstates, can be applied as earth-abundant photocatalytic materials for the degradation of persistent organic pollutants.

In this article, we studied the annealing process of AuCu layers deposited on TiO2 nanotubes (NTs) conducted in various atmospheres such as air, vacuum, argon, and hydrogen in order to obtain materials active in both visible and UV-vis ranges. The material fabrication route covers the electrochemical anodization of a Ti plate, followed by thin AuCu film magnetron sputtering and further thermal treatment. Scanning electron microscopy images confirmed the presence of spherical nanoparticles (NPs) formed on the external and internal walls of NTs. The optical and structural properties were characterized using UV-vis, X-ray diffraction, and X-ray photoelectron spectroscopies. It was proved that thermal processing under the argon atmosphere leads to the formation of a CuAuTi alloy in contrast to materials fabricated in air, vacuum, and hydrogen. The electrochemical measurements were carried out in NaOH using cyclic voltammetry, linear voltammetry, and chronoamperometry. The highest photoactivity was achieved for materials thermally treated in the argon atmosphere. In addition, the Mott-Schottky analysis was performed for bare TiO2 NTs and TiO2 NTs modified with gold copper NPs indicating a shift in the flatband potential. Overall, thermal processing resulted in changes in optical and structural properties as well as electrochemical and photoelectrochemical activities.

Communicated by Ramaswamy H. Sarma.

In this work, the effect of the addition of graphene oxide (GO) to nickel-iron (NiFe) and cobalt-nickel-iron (CoNiFe) mixed oxide/hydroxide/(oxy)hydroxide catalysts on their morphological, structural, and oxygen evolution reaction (OER) catalytic activity is investigated. The catalysts are fabricated during two-step electrodeposition: the first step includes the deposition of GO flakes, which in the second step become reduced with simultaneous deposition of NiFe or CoNiFe. As a result, NiFe-GO and CoNiFe-GO are fabricated without any additives directly on the nickel foam substrate. A significant improvement of the OER activity was observed after combining NiFe with GO (OER overpotential η(10 mA·cm-2): 210 mV) compared to NiFe (η: 235 mV) and GO (η: 320 mV) alone. Different OER activity was observed for CoNiFe-GO. Here, the overall catalytic activity (η: 230 mV) increased compared to GO alone, however it was reduced in comparison with the CoNiFe (η: 224 mV). The latter was associated with the change in the morphology and structure of the catalysts. Further OER studies show that each of the catalysts has a specific role in influencing the process: the improvement in the OER by NiFe-GO results mainly from the structure of NiFe and the electroactive surface area of GO.

In this article we present results of our follow-up studies of samples of watch glass obtained and examined within a framework of international intercomparison dosimetry project RENEB ILC 2021. We present three methods of dose reconstruction based on EPR measurements of these samples: calibration method (CM), added dose method (ADM) and added dose&heating method (ADHM). The study showed that the three methods of dose reconstruction gave reliable and similar results in 0.5–6.0 Gy dose range, with accuracy better than 10%. The ADHM is the only one applicable in a real scenario, when sample-specific background spectrum is not available; therefore, a positive verification of this method is important for future use of EPR dosimetry in glass in potential radiation accidents.

Development of environmentally friendly, high performing oxygen evolution reaction (OER) catalysts is an important research challenge. In this work, iron doped strontium titanates with a general formula SrTi1-xFexO3-δ (x = 0.35, 0.50, 0.70, 0.90, and 1.00) denoted as STFx, were synthesized via a solid state reaction technique and characterized in terms of oxygen evolution reaction electrocatalysis in an alkaline electrolyte (0.1 M KOH). The produced powders were characterized by a high specific surface area (>20 m2 g−1), beneficial for OER. The evaluation of specific activity indicated the following trend of increasing performance: STF35 < STF50 < STF70 < SFO < STF90. The lowest overpotential at 10 mAcm−2 GEO of 410 mV (350 mV at 25 μA cm−2OX) was achieved by STF90 with the corresponding Tafel slope of 60 mV dec−1. The two materials with the highest Fe content (i.e. STF90 and SFO) showed, however, poor chemical stability in alkaline solution demonstrated by the dissolution of Sr. Based on the good electrochemical performance (~460 mV at 10 mA cm−2GEO, ~405 mV at 25 μA cm−2OX) and chemical stability for at least 30 days (no Sr dissolution) of STF50, it can be considered an interesting, working at room temperature OER catalyst based on non-toxic and abundant elements.

In the present study, a hybrid photocatalyst of Zn/Ti layered double hydroxide (LDH) coupled with MXene - Ti

Organic aggregates currently play a prominent role, mainly for their unique optoelectronic properties in the aggregated state. Such properties can be related to the aggregates’ structure and the molecular packing mode. In the literature, we have well-established models of H and J aggregates defined based on the molecular exciton model. However, unconventional aggregates, the most unrecognized forms, have been generating interest among researchers recently. Within unconventional aggregation, aggregation-induced emission systems (AIE) are considered. In the present work, we discuss the effect of the forming of unconventional aggregation together with the change in dye concentration on the surface energy characteristics of the materials. All materials were prepared as hybrid biocompatible thin films where the matrix is TiO2 or TiO2/carbon nanowalls (CNWs) with the incorporated dye in the form of 1,8-diazafluoren-9-one (DFO). Using the time-resolved emission spectra and the determination of surface parameters from contact angle measurements, we indicated the correlation between the changes in such parameters and the concentration of DFO dye in two types of TiO2 and TiO2/CNW structures. To examine the propensity of DFO for aggregation, the internal energy of the dye was assessed in several aggregate structures using Quantum chemistry calculations. The results emphasize that DFO is an attractive structure in the design of new fluorophores due to its low molecular weight, the presence of a nitrogen atom that provides good coordination properties, and the ability to form hydrogen bonds. Our studies show that when using suitable matrices, i.e., rigid media, it forms the preferred forms of aggregates in the excited state, characterized by high emission efficiency in the band maximum of around 550 nm.

A free-standing high boron-doped diamond nanosheet (BDDNS) has been fabricated for the development of a flexible BDDNS strain senor. High boron-doped diamond was initially grown on a tantalum substrate in a microwave plasma-assisted chemical vapor deposition method, and was then transferred to a Kapton polymer substrate to fabricate the flexible BDDNS/Kapton device. Before performing the transfer process, the thin BDDNS’s morphology and bonding structure on the top and bottom surfaces were investigated using scanning electron microscopy and Raman spectroscopy. The contact potential difference and work function values of the BDDNS top and bottom surfaces were measured using a Kelvin probe atomic force microscope. Significant electrical conducting properties were observed from the resistance mapping of the BDDNS foil, and the average resistance value of 31 Ω attained from the top surface of the BDDNS foil. The electrical response of the BDDNS/Kapton device was investigated using a custom-made measurement system and a positive residual resistance change with strain was observed. The developed BDDNS/Kapton device was able to sustain for measuring up to 0.55% of strain, which indicates it may have great potential to be utilized in low-strain sensor applications.

Here, we report significant activity towards the oxygen evolution reaction (OER) of spherical nickel nanoparticles (NPs) electrodeposited onto free-standing TiO2 nanotubes (TNT) via cyclic voltammetry. It has been shown that simple manipulation of processing parameters, including scan rate and number of cycles, allows for formation of the NPs in various diameters and amounts. The polarization data with respect to transmission electron microscopy (TEM) allowed for determination of the diameter and propagation depth of the Ni NPs leading to the highest activity towards the OER with an overpotential of 540 mV at +10 mA cm−2 and Tafel slope of 52 mV per decade. X-ray photoelectron spectroscopy (XPS) indicates the presence of structure defects within Ni NPs whereas Mott–Schottky analysis provides information on the anodically shifted flat band potential and highly increased donor density. The obtained results along with literature studies allowed a proposal of the origin of the enhancement towards the OER. We believe that combination of transition metal-based NPs and TNT provides valuable insight on efficient and low-cost electrocatalysts.

Spinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical conductivity, thermal expansion, and sinterability behaviour. The results show that the Fe content has a significant influence on the phase composition and the resulting properties. Characterisation of the dilatometry and conductivity coupled with XRD phase analysis across a wide temperature range allowed the relations between the materials properties and compositions to be observed. The results indicate that Mn1.7Cu0.8Fe0.5O4 is a promising material for use as a protective coating for interconnects in intermediate temperature Solid Oxide Fuel Cells.

Ce0.8Gd0.2O1.9 (CGO) barrier layers are required to mitigate the chemical reactions between Sr-containing oxygen electrode materials and Zr-based oxygen ion conductors in high-temperature solid oxide cells. Barrier layers produced by different methods were studied in this work. As a reference, a cell with no barrier layer was measured. The application of the powder-processed barrier layers, considerably increases the performance. For further comparison, thin and dense CGO layers were produced by a low-temperature spray pyrolysis process. Three different thicknesses were evaluated: ∼300 nm, ∼700 nm and ∼1500 nm. The best performance was found for the ∼700 nm thick CGO barrier layer. It showed low ohmic and polarisation resistances. The low thickness and high density of the CGO barrier layer were found to be the important factors. The cells with the ∼700 nm CGO barrier layers were also evaluated for their electrolysis performance as well as fuel cell durability.

A very important method of reducing the amount of polymer waste in the environment is the introduction to the market of polymers susceptible to degradation under the influence of environmental factors. This paper presents the results of testing the susceptibility to degradation in soil of branched polyesterurethane (PUR) based on poly([R,S]-3-hydroxybutyrate) (R,S-PHB), modified with poly([D,L]-lactide) (PLA) and starch (St). Weight losses of samples and changes in surface morphology (SEM, OM and contact angle system) with simultaneously only slight changes in molecular weight (GPC), chemical structure (FTIR and 1HNMR) and thermal properties (DSC) indicate that these materials are subject to enzymatic degradation caused by the presence of microorganisms in the soil. Chemical modification of branched polyesterurethanes with R,S-PHB and their physical blending with small amounts of PLA and St resulted in a slow but progressive degradation of the samples.

Protein fibrillation leads to formation of amyloids—linear aggregates that are hallmarks of many serious diseases, including Alzheimer’s and Parkinson’s diseases. In this work, we investigate the fibrillation of a short peptide (K-peptide) from the amyloidogenic core of hen egg white lysozyme in the presence of dimethyl sulfoxide or urea. During the studies, a variety of spectroscopic methods were used: fluorescence spectroscopy and the Thioflavin T assay, circular dichroism, Fourier-transform infrared spectroscopy, optical density measurements, dynamic light scattering and intrinsic fluorescence. Additionally, the presence of amyloids was confirmed by atomic force microscopy. The obtained results show that the K-peptide is highly prone to form fibrillar aggregates. The measurements also confirm the weak impact of dimethyl sulfoxide on peptide fibrillation and distinct influence of urea. We believe that the K-peptide has higher amyloidogenic propensity than the whole protein, i.e., hen egg white lysozyme, most likely due to the lack of the first step of amyloidogenesis—partial unfolding of the native structure. Urea influences the second step of K-peptide amyloidogenesis, i.e., folding into amyloids.

We proposed fast and scalable route where the ordered TiO2 nanotubes coated with thin copper layers were annealed by the laser beam of 355 nm wavelength at different fluencies in the range of 15–120 mJ/cm2. As a result, copper species are integrated with the titania substrate and the formed material exhibits unique optical absorption bands in the visible range. Moreover, X-ray photoelectron spectroscopy analysis reveals the formation of Cu2O while the 4+ oxidation state of titanium is preserved. According to the electrochemical results, the material treated by laser exhibits outstanding photoelectrochemical activity comparing to the pristine titania or the one only covered by the thin copper film. In particular, when the fluence of 60 mJ/cm2 was used for the modification of the titania decorated with Cu film, the current density recorded in KOH electrolyte reaches nearly 4.5 mA/cm2 at +2.0 V vs. Ag/AgCl/0.1 M KCl upon visible light.

Titanium dioxide nanotubes gain considerable attention as a photoactive material due to chemical stability, photocorrosion resistance, or low-cost manufacturing method. This work presents scalable pulsed laser modification of TiO2 nanotubes resulting in enhanced photoactivity in a system equipped with a motorized table, which allows for modifications of both precisely selected and any-large sample area. Images obtained from scanning electron microscopy along with Raman and UV-vis spectra of laser-treated samples in a good agreement indicate the presence of additional laser-induced shallow states within band gap via degradation of crystalline structure. However, X-ray photoelectron spectroscopy spectra revealed no change of chemical nature of the modified sample surface. Photoelectrochemical measurements demonstrate superior photoresponse of laser-treated samples up to 1.45-fold for an energy beam fluence of 40 mJ/cm2 compared to that of calcined one. According to the obtained results, optimal processing parameters were captured. Mott-Schottky analysis obtained from impedance measurements indicates an enormous (over an order of magnitude) increase of donor density along with a +0.74 V positive shift of flat band potential. Such changes in electronic structure are most likely responsible for enhanced photoactivity. Thus, the elaborated method of laser nanostructuring can be successfully employed to the large-scale modification of titania nanotubes resulting in their superior photoactivity. According to that, the results of our work provide a contribution to wider applications of materials based on titania nanotubes.

Even in the 21st century, chronic wounds still pose a major challenge due to potentially inappropriate treatment options, so the latest wound dressings are hybrid systems that enable clinical management, such as a hybrid of hydrogels, antibiotics and polymers. These wound dressings are mainly used for chronic and complex wounds, which can easily be infected by bacteria.Six Composite Porous Matrices (CPMs) based on polyurethane (PUR) in alliance with polylactide (PLAs) and poly(vinyl alcohol) (PVA) were prepared and analyzed using optical microscopy. Three different types of hydrogels and their Ciprofloxacin (Cipro) modified variants' ratios were prepared and analyzed using FTIR, SEM and EDX techniques. Six Hybrid Cipro-Releasing Hydrogel Wound Dressings (H-CRWDs) were also prepared and underwent short-term degradation, Cipro release, microbiology and cell viability measurements.Average porosity of CPMs was in the range of 69-81%. The pore size of the obtained CPMs was optimal for skin regeneration. Short-term degradation studies revealed degradability in physiological conditions regardless of sample type. A meaningful release was also observed even in short time (21.76 ​± ​0.64 ​μg/mL after 15 ​min). Microbiological tests showed visible inhibition zones. Cell viability tests proved that the obtained H-CRWDs were biocompatible (over 85% of cells).A promising hybrid wound dressing was labeled. Simple and cost-effective methods were used to obtain microbiologically active and biocompatible dressings. The results were of importance for the design and development of acceptable solutions in the management of chronic wounds of high potential for infection.

In this article, we studied the annealing process of AuCu layers deposited on TiO

This work focuses on the fabrication of non-enzymatic glucose sensing materials based on laser-formed Au nanoparticles embedded in Ti-textured substrates. Those materials possess good catalytic activity toward glucose oxidation in 0.1 × phosphate buffered saline as well as resistance to some interferants, such as ascorbic acid, urea, and glycine. The electrodes are further coated with three different polymers, that is, Nafion, photo-crosslinked poly(zwitterions) based on sulfobetaine methacrylate, and a hybrid membrane consisting of both polymers. Both the optimal integrity of the material and its catalytic activity toward glucose oxidation were maintained by the hybrid membranes with a large excess of poly(zwitterions) (mass ratio 20:1). The chemical structures of the as-formed membranes are confirmed by Fourier transform infrared spectroscopy. Due to the zwitterionic nature of the coating, the electrodes are resistant to biofouling and maintain electrochemical activity toward glucose for 4 days. Moreover, due to the synergistic effect of both Nafion and poly(zwitterions), the interference from the two compounds, namely, from acetylsalicylic acid and acetaminophen, was diminished. Besides the presence of polymer membranes, the electrode possesses a sensitivity of 36.8 μA cm-2 mM-1 in the linear range of 0.4-12 mM, while the limit of detection was estimated to be 23 μM. Finally, the electrodes are stable, and their response is not altered even by 1,000 bending cycles.

In the present study, a novel Fe-ZnO/citric acid-modified cellulose composite (x%Fe-ZnO-y%CAC) was synthesized using an environmentally friendly hydrothermal method. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FTIR), nitrogen physisorption, and electrochemical and photocurrent density analyses. The influence of the additives from the series of x%Fe-ZnO-y%CAC photocatalysts with Fe content from 0 to 5% and CAC content from 0 to 80% on photocatalytic degradation of ibuprofen (IBU) under simulated solar light was investigated. The photocatalyst 0.5%Fe-ZnO-40%CAC showed high photocatalytic activity of 0.0632 min−1 first-order kinetic rate constant and 46% TOC reduction of IBU under simulated solar light irradiation. Additionally, H2O2-assisted photocatalytic process was investigated for facilitating the IBU degradation in the presence of 0.5%Fe-ZnO-40%CAC; the first-order kinetic rate constant was 2.7 times higher compared to the process without addition of H2O2. Moreover, the effect of radical scavengers was examined to explain the degradation mechanism of IBU by synthesized photocatalysts supported with H2O2. The demonstrated system provides a low-cost and green approach to improve the photocatalytic activity of x%Fe-ZnO-y%CAC photocatalysts.

The use of shrimp waste to obtain chitosan (Ch) is an essential issue, considering a circular economy, waste management, and its application to environmentally friendly materials. In this study, northern prawn shells were utilized to obtain Ch, which could then be used for synthesizing chitosan-based polyurethane (PUR+Ch) foams with different Ch concentration. The chemical structure, morphology, hardness, thermal properties, viscoelastic properties, and sorption properties in relation to oil and water of these materials were determined. The results present that the addition of Ch into PUR influences the physicochemical characteristics and properties of the tested materials. PUR+Ch foams with 1–3 wt% Ch had more open cells and were softer than neat PUR. PUR+Ch1 had the best thermal properties. PUR+Ch2 foam with 2 wt% Ch as a whole was characterized as having the highest water sorption. The PUR+Ch1 foam with 1 wt% Ch had the best oil sorption. This paper shows that the modification of PUR by Ch is a very promising solution, and PUR+Ch foams can be applied in the water treatment of oil spills, which can be dangerous to the water environment.