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Highly phosphorylated cellulose was produced under different processing parameters and used as an effective adsorbent for methylene blue (MB) dye removal from aqueous systems. The characteristics of the designed adsorbent were analyzed using different technics. The zeta potential measurement of the developed adsorbents was negative (-11.3 to -49.4 mV) in the pH range of 4 to 11. Batch removal tests were performed under different processing parameters of contact time, initial concentration, phosphorylation degree and pH. The developed adsorbent with a high substitution degree of 1.07 (13.22 % of P), revealed an outstanding retention capacity for MB dye (up to 3153.5 mg/g) during an extremely low equilibrium adsorption time (∼30 min), which is 130-fold higher than pure MCC (15.3 mg/g). Interestingly, this capacity raised up to 3236.6 mg/g when raising the pH of the solution (from 7 to 11). The experimental adsorption data in the examined conditions were well fitted by the Langmuir type isotherm and pseudo-second-order kinetic models, highlighting the significance of the reaction medium and phosphate content in determining the adsorbent's retention capacity. This investigation has demonstrated the potential of converting pure MCC into high value-added adsorbent for the efficient purification of organic dye from aqueous solutions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The integration of metal oxides onto two-dimensional layered siloxene has proven to be an effective strategy for expanding potential applications across diverse fields. Herein, we present the synthesis and detailed characterization of zinc oxide (ZnO) nanorods deposited on siloxene nanosheets using the wet chemical precipitation method without the need of alkali. The presence of ZnO nanorods was confirmed through electron microscopy analyses. X-ray diffraction analysis further verified the presence of characteristic peaks of ZnO in the hexagonal wurtzite crystal structure. Dielectric measurements demonstrated the moderated stability of interfacial polarization in siloxene nanosheets doped with zinc oxide (SX-ZnO) over a broad frequency spectrum, coupled with minimal electrical loss values under 0.4 within the 100 Hz to 1 MHz frequency range. In addition, the ferroelectric study of SiNSs-ZnO composites revealed a slim hysteresis loop with maximum polarization and remnant polarization values that varied with reaction times. The SX-ZnO sample prepared for 5 h exhibited the best stored energy properties, featuring a moderate stored energy density ( W s ) and a high energy efficiency of 83.38%. This investigation underscores that the modification of siloxene layers through the deposition of nanostructured transition metal oxide materials leads to stabilized interfacial polarization and enhanced efficient energy storage.-3 ) and a high energy efficiency of 83.38%. This investigation underscores that the modification of siloxene layers through the deposition of nanostructured transition metal oxide materials leads to stabilized interfacial polarization and enhanced efficient energy storage., Competing Interests: The authors claim that they have no personal conflict of interest that could influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Recycling solid industrial wastes into valuable materials is always the priority solution in waste management. In this perspective, sugar scum and fly ash were used to produce an effective low-cost porous ceramic membrane. The impacts of the sintering temperature, amount of sugar scum, and sintering time on the properties of the prepared ceramic membrane were investigated and optimized using experimental design. A simultaneous rise in both the sintering temperature and the amount of sugar scum leads to a notable increase in porosity. Moreover, the simultaneous increase or decrease in the time and the amount of sugar scum causes a significant decrease in the compressive strength. The optimal conditions have been determined as a sintering temperature of 1197 °C, a sugar scum amount of 12.06 %, and a sintering time of 253 min. Under these conditions, the density, porosity, and compressive strength were found to be 2.16 g/cm³, 34.66 %, and 28.24 MPa, respectively. In addition, the obtained ceramic membrane has a water permeability of 2356.68 L/h m 2  bar, a pore size in the range 0-4.5 μm, and excellent chemical resistance in both acidic and basic media. Finally, the performance of the prepared ceramic membrane was evaluated by the filtration of methylene blue. The results indicate that sugar scum and fly ash are suitable precursors to manufacture an effective ceramic membrane for the treatment of wastewater., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Wear (erosion/abrasion) and corrosion act in synergy in several industrial installations where corrosive fluids circulate together with a solid phase causing mutual damage. High entropy alloys (HEAs) are promising materials to be used in that type of environments because of their outstanding chemical, electrochemical and mechanical properties. While several review articles are currently available on corrosion, mechanical properties, development of HEAs, microstructure, and HEA coatings, there is an undeniable lack of a comprehensive and critical review focusing on the tribological behaviour and tribocorrosion of bulk HEAs. This work aims to collect, summarise, and critically review the major accomplishments and progresses of HEAs over the last 20 years dealing with wear, corrosion, and wear-corrosion resistance. It highlights the most significant aspects that can influence the performance of HEAs including the change of the base alloying elements, the influence of the temperature, heat treatment, and wear test parameters (load, velocity, duration, distance). Furthermore, operating mechanisms, together with the relationship between microstructure and wear resistance, and between microstructure and corrosion resistance will be described. Finally, the articles that have been reported in the literature dealing with tribocorrosion of HEAs will be reviewed. The results of this study are expected to guide potential researchers and provide them with the sum of current trends in HEAs in terms of corrosion resistance, wear resistance and the synergy of both, in the hope of helping them to make the right decision to design and develop new HEAs or improve the research on the existing ones., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Two eco-friendly and highly efficient adsorbents, namely brushite-chitosan (DCPD-CS), and monetite-chitosan (DCPA-CS) composites were synthesized via a simple and low-cost method and used for tetracycline (TTC) removal. The removal behavior of TTC onto the composite particles was studied considering various parameters, including contact time, pollutant concentration, and pH. The maximum TTC adsorption capacity was 138.56 and 112.48 mg/g for the DCPD-CS and DCPA-CS, respectively. Increasing the pH to 11 significantly enhanced the adsorption capacity to 223.84 mg/g for DCPD-CS and 205.92 mg/g for DCPA-CS. The antibiotic adsorption process was well-fitted by the pseudo-second-order kinetic and Langmuir isotherm models. Electrostatic attractions, complexation, and hydrogen bonding are the main mechanisms governing the TTC removal process. Desorption tests demonstrated that the (NH 4 ) 2 HPO 4 solution was the most effective desorbing agent. The developed composites were more efficient than DCPD and DCPA reference samples and could be used as valuable adsorbents of TTC from contaminated wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Hydroxyapatite (HA) and chitosan (CS) biopolymer are the major materials investigated for biomedical purposes. Both of these components play an important role in the orthopedic field as bone substitutes or drug release systems. Used separately, the hydroxyapatite is quite fragile, while CS mechanical strength is very weak. Therefore, a combination of HA and CS polymer is used, which provides excellent mechanical performance with high biocompatibility and biomimetic capacity. Moreover, the porous structure and reactivity of the hydroxyapatite-chitosan (HA-CS) composite allow their application not only as a bone repair but also as a drug delivery system providing controlled drug release directly to the bone site. These features make biomimetic HA-CS composite a subject of interest for many researchers. Through this review, we provide the important recent achievements in the development of HA-CS composites, focusing on manufacturing techniques, conventional and novel three-dimensional bioprinting technology, and physicochemical and biological properties. The drug delivery properties and the most relevant biomedical applications of the HA-CS composite scaffolds are also presented. Finally, alternative approaches are proposed to develop HA composites with the aim to improve their physicochemical, mechanical, and biological properties., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

This work aims to develop an injectable and antibacterial composite cement for bone substitution and prevention/treatment of bone infections. This cement is composed of calcium phosphate, calcium carbonate, bioactive glass, sodium alginate, and ciprofloxacin. The effect of ciprofloxacin on the microstructure, chemical composition, setting properties, cohesion, injectability, and compressive strength was investigated. The in vitro drug release kinetics and the antibacterial activity of ciprofloxacin-loaded composites against staphylococcus aureus and Escherichia coli pathogens were investigated. XRD and FTIR analysis demonstrated that the formulated cements are composed of a nanocrystalline carbonated apatite analogous to the mineral part of the bone. The evaluation of the composite cement's properties revealed that the incorporation of 3 and 9 wt% of ciprofloxacin affects the microstructural and physicochemical properties of the cement, resulting in a prolonged setting time, and a slight decrease in injectability and compressive strength. The in vitro drug release study revealed sustained release profiles over 18 days. The amounts of ciprofloxacin released per day (0.2 -15.2 mg/L) depend on the cement composition and the amount of ciprofloxacin incorporated. The antibacterial activity of ciprofloxacin-loaded cement composites attested to their effectiveness to inhibit the growth of Staphylococcus aureus and Escherichia coli., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The leaching of rare earth elements (REEs) from secondary resources is exponentially increasing to supply the widespread range of high-tech applications of these elements including phosphors lighting materials, catalysis and permanent magnets. Phosphate fertilizer byproducts including phosphogypsum (PG) were identified as a potential alternative resource of REEs, not only to face the expansion of market demand, but also to achieve a sustainable management of REE resources. This study reports the leaching of REEs from PG using methanesulfonic acid (MSA) as a green organo-sulfonic acid in comparison with other acids such as p -toluenesulfonic acid (PTSA) and hydrochloric acid (HCl). MSA achieved the highest leaching efficiency of 78% with low solubility of PG under the operating conditions of 3 M, solid to liquid ratio (S/L) of 1/8, 120 min and 25 °C. The optimized leaching process was also modeled using shrinking core theory to assess the kinetics behavior of the system and to enable the determination of the predominant mechanisms. It was demonstrated that the leaching is governed by a product layer diffusion-controlled model with an activation energy of 2.73 kJ mol -1 . The cleaned PG after leaching could greatly meet the quality requirements of the building materials industry., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Herein, bio-based alginates (Alg) containing metallic beads (Ce and Cu) were synthesized via an alginate cross-linking method, and their properties were studied using experimental techniques combined with theoretical simulations. Materials were characterized through Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscope (SEM) images, to determine the cross-linking structural features, thermal stability, and surface morphology of alginates. Besides, density functional theory (DFT) methods were employed to calculate global reactivity parameters such as HOMO-LUMO gap energies (ΔE H-L ), electronegativity (χ), hardness (η), and electrophilic and nucleophilic indicators, using both gas and aqueous media for the study of the complexation process. Among other features, characterization of the thermal properties showed that Alg@Ce and Alg@Cu alginate beads behave differently as a function of the temperature. This behavior was also predicted by the conformation energy differences between Alg@Ce and Alg@Cu, which were found out theoretically and explained with the combined study of the vibrational modes between the carboxylate group with either Ce or Cu. Overall, the reactivity of the Alg@Ce alginate bead was higher than that of the Alg@Cu counterpart, results could be used as a cornerstone to employed the materials here studied in a wide range of applications., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)