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MBenes are post‐MXene materials that contain boron in their structure instead of carbon and nitrogen. This unique composition offers an opportunity to explore the role of boron in the performance of 2D materials. However, wet‐chemical etching and delamination of the starting MoAlB phase are challenging due to the persistent bonding of aluminum atoms with their neighboring elements. Herein, it is overcome by processing MoAlB for 24, 48, and 72 h with an aqueous HCl/H2O2 solution. The time‐wise etching and delamination delivers individual single‐to‐few layered 48‐MBene flakes. The theoretical‐to‐experimental XRD analysis revealed the best‐delaminated 48‐MBene having Mo2B2 orthorhombic lattice arrangement. The presence of Mo oxide allows direct 1.2 eV and indirect 0.2 eV optical band gaps and outstanding photocatalytic activity in decomposing methylene blue as a model organic contaminant. The 48‐MBene photocatalyst achieves about 90% of MB decomposition under ultraviolet and simulated white light irradiation with three times faster kinetics outperforming even hybridized MXenes. In addition, 48‐MBene appeared best suited to utilize the full spectrum of visible light into reactive oxygen species. Conversely, 24‐MBene and 72‐MBene shows incomplete delamination or oxidation, hampering their photocatalytic activity. The obtained results open an experimental pathway to apply MBenes in environmental remediation. [ABSTRACT FROM AUTHOR]

Two‐dimensional MXenes are excellent photocatalysts. However, their low oxidation stability makes controlling photocatalytic processes challenging. For the first time, this work elucidates the influence of the oxidation stabilization of model 2D Ti3C2Tx MXene on its optical and photocatalytic properties. The delaminated MXene is synthesized via two well‐established approaches: hydrofluoric acid/tetramethylammonium hydroxide (TMAOH‐MXene) and minimum intensive layer delamination with hydrochloric acid/lithium fluoride (MILD‐MXene) and then stabilized by L‐ascorbic acid. Both MXenes at a minimal concentration of 32 mg L−1 show almost 100% effectiveness in the 180‐min photocatalytic decomposition of 25 mg L−1 model methylene blue and bromocresol green dyes. Industrial viability is achieved by decomposing a commercial textile dye having 100 times higher concentration than that of model dyes. In such conditions, MILD‐MXene is the most efficient due to less wide optical band gap than TMAOH‐MXene. The MILD‐MXene required only few seconds of UV light, simulated white light, or 500 nm (cyan) light irradiation to fully decompose the dye. The photocatalytic mechanism of action is associated with the interplay between surface dye adsorption and the reactive oxygen species generated by MXene under light irradiation. Importantly, both MXenes are successfully reused and retained approximately 70% of their activity. [ABSTRACT FROM AUTHOR]

In an era of increasing environmental awareness, it is very important to work towards eliminating or at least reducing as many harmful industrial substances as possible. However, the implementation of green chemistry methods for wastewater treatment can be difficult especially due to complexity, the high cost of reagents, and the required long process time. This paper focuses on using waste iron (WI) to remove two kinds of amaranth dye commonly used in industry. To enhance the process, UV irradiation and hydrogen peroxide were used. The novelty of the research was the use of efficient and reusable WI as a heterogeneous catalyst in the process. WI material characteristics was done before and after the process using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF). Zeta potential, size characterization, circularity, and direct band gap were also determined. As a result of treatment complete decolorization of both dyes was achieved, as well as 99% absorbance removal after 15-min process time. The total organic carbon (TOC) decrease after 60-min process time was in the range from 86.6 to 89.8%. Modified pseudo-second-order reaction reflects obtained results of treatment efficiency. Treatment results, confirmed by WI material characterization, indicate satisfactory stability of the catalyst and good oxidation capacity. [ABSTRACT FROM AUTHOR]

Dyes are highly toxic and persistent in the environment. Their presence in water causes environmental and social problems. Dyes must be effectively removed from the water. A UV/ZVI/H2O2 process was applied to decompose two organic dyes, AM E123 and AM ACID. A commercial ZVI product, Ferox Flow, was used, and its properties were determined using SEM and XRF. The zeta potential, surface area, and optical properties of ZVI were also determined. The efficiency of dye removal in optimal conditions was 85.5% and 80.85% for AM E123 and AM ACID, respectively. Complete decolorization was observed in all samples. The decomposition of both dyes occurred according to a modified pseudo-second-order reaction and there was a statistically significant correlation between the TOC decrease, pH, and process time. The catalyst was observed to have high stability, and this was not affected by the performance of the treatment process even after the third cycle, as confirmed by the results of the catalyst surface analysis and iron diffusion test. Slight differences in process efficiency were observed after each cycle. The need for only a small amount of catalyst to decompose AM E123 and AM ACID, coupled with the ability to reuse the catalyst without the need for prior preparation, may reduce catalyst purchase costs. [ABSTRACT FROM AUTHOR]

Rapidly developing nanotechnologies and their integration in daily applications may threaten the natural environment. While green methods of decomposing organic pollutants have reached maturity, remediation of inorganic crystalline contaminants is major problem due to their low biotransformation susceptibility and the lack of understanding of material surface-organism interactions. Herein, we have used model inorganic 2D Nb-based MXenes coupled with a facile shape parameters analysis approach to track the mechanism of bioremediating 2D ceramic nanomaterials with green microalgae Raphidocelis subcapitata. We have found that microalgae decomposed the Nb-based MXenes due to surface-related physicochemical interactions. Initially, single and few-layered MXene nanoflakes attached to microalgae surfaces, which slightly reduced algal growth. But with prolonged surface interaction, the microalgae oxidized MXene nanoflakes and further decomposed them into NbO and Nb2O5. Since these oxides were nontoxic to microalgal cells, they consumed Nb-oxide nanoparticles by an uptake mechanism thus enabling further microalgae recovery after 72 h of water treatment. The uptake-associated nutritional effects were also reflected by cells' increased size, smoothed shape and changed growth rates. Based on these findings, we conclude that short- and long-term presence of Nb-based MXenes in freshwater ecosystems might cause only negligible environmental effects. Notably, by using 2D nanomaterials as a model system, we show evidence of the possibility of tracking even fine material shape transformations. In general, this study answers an important fundamental question about the surface interaction-associated processes that drive the mechanism of 2D nanomaterials' bioremediation as well as provides the fundamental basis for further short- and long-term investigations on the environmental effects of inorganic crystalline nanomaterials. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a thermoplastic polymer widely used as a medical textile in healthcare applications due to its low cost and superior performance. However, it does not show antibacterial properties leading to the possibility of pathogen transmission. Herein, we have developed an antibacterial medical fabric by facile self-assembly of delaminated two-dimensional (2D) Ti3C2Tx MXene flakes bristling on the surface of PP fibers. The increasing amount of MXene in the coating solution from 1 up to 32 mg/mL allowed for edge-on assembly of MXene flakes on the PP surface and tracking the evolution of the band gap for a restacked structure. Characterization of the PP/Ti3C2Tx nanocomposite has proven that it exhibited highly effective antibacterial, robust coating, and chemically/thermally stable properties. The in vitro microbiological studies against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus have shown that PP/Ti3C2Tx reduced the bacterial viability up to 100%, as driven by synergistic membrane stress mediated by physical contact and light-induced reactive oxygen species (ROS) generation. Moreover, the use of l-ascorbic acid for MXene stabilization allowed for achieving excellent thermal stability of the PP/Ti3C2Tx nanocomposite upon accelerated thermal aging. Collectively, this work provides a facile surface engineering strategy for designing medical fabrics with outstanding functional performances. By demonstrating the exceptional performance of the stabilized MXene in a self-assembly nanocomposite structure, we are opening the door for MXenes to be applied in other biomedical fields. [ABSTRACT FROM AUTHOR]

Two-dimensional compounds with nanostructural features are attracting attention from researchers worldwide. Their multitude of applications in various fields and vast potential for future technology advancements are successively increasing the research progress. Wastewater treatment and preventing dangerous substances from entering the environment have become important aspects due to the increasing environmental awareness, and increasing consumer demands have resulted in the appearance of new, often nonbiodegradable compounds. In this review, we focus on using the most promising 2D materials, such as MXenes, Bi2WO6, and MOFs, as catalysts in the modification of the Fenton process to degrade nonbiodegradable compounds. We analyze the efficiency of the process, its toxicity, previous environmental applications, and the stability and reusability of the catalyst. We also discuss the catalyst's mechanisms of action. Collectively, this work provides insight into the possibility of implementing 2D material-based catalysts for industrial and urban wastewater treatment. [ABSTRACT FROM AUTHOR]

Due to the presence of multiple caves and rock shelters as well as flint outcrops, Ojców Upland is a region with an exceptionally high concentration of prehistoric human settlement traces. It has attracted archaeologists for over 150 years, leading to what was considered to have been a proper prospection of the area. Nonetheless, the analysis of airborne laser scanning has recently brought surprising results. In the very centre of the upland, on the densely forested hill 'Złota Góra' (Golden Hill), the remains of an exceptionally large defensive structure in the form of several rows of embankments were found. The use of magnetic methods made it possible to confirm their anthropogenic origin and the likely type of embankment construction. In turn, the layout of embankments combined with the results of a surface survey and the analyses of the acquired artefacts and the settlement context speak in favour of linking this defensive structure with a high degree of probability with the Neolithic or Eneolithic, most likely the Lengyel‐Polgár cycle or Baden culture. The presence of such a large fortification in the immediate vicinity of flint mines could shed new light on the image of the Late Neolithic‐Early/Middle Eneolithic period in this part of Europe. [ABSTRACT FROM AUTHOR]

2D transition metal borides (MBenes) have emerged as promising post‐MXene materials with potential application in various biotechnological fields. Although they possess prospective bioactive properties due to boron in their structure, the experience gained from MXenes shows that an in‐depth understanding of their biological recognition and response as well as the exploration of their biological applications are highly challenging. This makes the identification of the most promising 2D MBenes for future biological research and final industrial applications rather complicated. Herein, MBenes are differentiated from MXenes and further untangled for their bioactivity‐generating features. It is expected that MBenes' positive or negative biological impact on living organisms and different types of cells connect with their morphological, structural and physicochemical features in the context of relevant environments. Necessary toxicological data are also highlighted, which are key aspects to enable MBenes' safe application in biotechnology and nanomedicine. Furthermore, a perspective for the rational development and design of novel biotechnological solutions based on MBenes is provided, which will meet the legal safety requirements for nanomaterials. In this regard, this work is an unprecedented contribution toward strategies for regulatory development for MBene/MXene‐type nanomaterials. It provides an inspiration for future biotechnological and nanotoxicological approaches using MBenes. [ABSTRACT FROM AUTHOR]

Copyright of Materiały Zachodniopomorskie: Annual Science Journal of National Museum in Szczecin is the property of Muzeum Narodowe w Szczecinie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Archaeologica Lodziensia is the property of Lodz Scientific Society / Lodzkie Towarzystwo Naukowe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, NiTi alloy parts were fabricated using laser powder bed fusion (LBPF) from pre-alloyed NiTi powder and in situ alloyed pure Ni and Ti powders. Comparative research on the corrosive and biological properties of both studied materials was performed. Electrochemical corrosion tests were carried out in phosphate buffered saline at 37 °C, and the degradation rate of the materials was described based on Ni ion release measurements. Cytotoxicity, bacterial growth, and adhesion to the surface of the fabricated coupons were evaluated using L929 cells and spherical Escherichia coli (E. coli) bacteria, respectively. The in situ alloyed NiTi parts exhibit slightly lower corrosion resistance in phosphate buffered saline solution than pre-alloyed NiTi. Moreover, the passive layer formed on in situ alloyed NiTi is weaker than the one formed on the NiTi fabricated from pre-alloyed NiTi powder. Furthermore, in situ alloyed NiTi and NiTi made from pre-alloyed powders have comparable cytotoxicity and biological properties. Overall, the research has shown that nitinol sintered using in situ alloyed pure Ni and Ti is potentially useful for biomedical applications. [ABSTRACT FROM AUTHOR]

Point-of-use (POU) water treatment systems and devices play an essential role in limited access to sanitary safe water resources. The filtering materials applied in POU systems must effectively eliminate contaminants, be readily produced and stable, and avoid secondary contamination of the treated water. We report an innovative, 2D Ti3C2/Al2O3/Ag/Cu nanocomposite-modified filtration material with the application potential for POU water treatment. The material is characterized by improved filtration velocity relative to an unmodified reference material, effective elimination of microorganisms, and self-disinfecting potential, which afforded the collection of 99.6% of bacteria in the filter. The effect was obtained with nanocomposite levels as low as 1%. Surface oxidation of the modified material increased its antimicrobial efficiency. No secondary release of the nanocomposites into the filtrate was observed and confirmed the stability of the material and its suitability for practical application in water treatment. [ABSTRACT FROM AUTHOR]