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The purpose of this paper is the modification of a carbon paste electrode (CPE) with activated carbon synthesized from date stones using a pyrolysis system followed by physical activation. This material has the advantage of very low cost and facilitates charge transfer. The modified electrode was used for electrocatalysis and determination of catechol. A series of analyses and tests were carried out to demonstrate the nature, the surface functional groups and even the porosity of the resulting product. The activated carbon exhibited remarkable electrocatalytic activity toward catechol oxidation. The electron transfer coefficient, surface coverage and number of electrons for catechol oxidation at the surface of the AC-CPE were determined using electrochemical approaches. Subsequently, a sensitive and convenient electrochemical method was proposed for catechol analysis. The linear range is between 1.0 × 10−6 and 1.0 × 10−3 mol L−1 with a correlation coefficient of 0.993. The limit of detection is as low as 4.8 × 10−8 mol L−1. Finally, this novel method was employed to determine the catechol in tap water, green, black and peach teas, and in coffee samples. [ABSTRACT FROM AUTHOR]

This study offers a novel method for improving the piezoelectric characteristics of polyvinylidene fluoride (PVDF) by adding lanthanated CoFe 2 O 4 nanoparticles (CLFO), thereby addressing the critical need for effective renewable energy solutions. The novelty of this work lies in the synthesis of CLFO nanoparticles and their integration into the PVDF matrix, with polyvinylpyrrolidone (PVP) employed to ensure uniform dispersion. This was accomplished by a special co-precipitation and heat treatment procedure. Nanocomposite films were created using solvent casting with a range of CLFO concentrations (1, 3, 5, and 7 wt%). The structural, morphological, mechanical, and thermal properties of these films were all thoroughly assessed. A remarkable improvement over conventional techniques was found using X-ray diffraction and Fourier transform infrared spectroscopy, which showed up to 80% β-phase development with 3 wt% CLFO. While thermogravimetric studies showed enhanced thermal stability, scanning electron microscopy verified homogeneous nanoparticle dispersion. Mechanical tests revealed ideal stiffness, strength, and ductility at 3 wt% CLFO. Significant advances in electronics and energy harvesting are anticipated from this novel combination of PVDF's piezoelectric properties and CLFO reinforcement. By minimally influencing the environment, these advancements not only tackle the world's energy problems but also present prospective uses for renewable energy technologies., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Soft magnetic materials, like Ni 0.5 Zn 0.5 Fe 2 O 4 , require high temperatures and regulated environments for their manufacture and processing, which can be highly energy intensive. These requirements therefore result in higher production costs and energy consumption. To address this issue, the development of composite materials based on soft magnetic ferrites has become a prominent research area. The type of particles and their size distribution, shape, and dispersion within the polymer matrix can be crucial for controlling the magnetic properties. In this context, and to reduce energy consumption, the parameters of solid-state reaction (such as calcination temperature, calcination time, and milling time) were optimized in this work to produce magnetic particles with suitable shape and size for filling a thermoplastic matrix. The impact of these parameters on phase purity, morphology, particle size, and magnetic properties was thoroughly evaluated. The results highlight that the sample synthesized at 1200 °C for 6 hours achieved an impressive saturation magnetization value of 80.07 emu g -1 , showcasing exceptional magnetic performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

With the increasing demand of new magnetic materials for modern technological application alternatives to conventional magnetic materials, the development of lightweight polymer magnetic composites has become a prominent research area. For this perspective, a new magnetic material was developed using 30 wt% nickel ferrite micro and nanoparticles as fillers for a high-density polyethylene matrix. The development process began with the synthesis of NF-micro and NF-nanoparticles using solid-state and co-precipitation techniques, respectively, followed by extrusion molding and injection molding. The success of the synthesis process and the purity of the spinel structure phase were confirmed. Additionally, using the extrusion process produced polymer magnetic composite materials with a good distribution of magnetic particles within the polymer matrix, resulting in good magnetic properties and enhanced mechanical properties of the polymer magnetic materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Hemp is known for its swift growth and remarkable sustainability, requiring significantly less water, an adaptable cultivation to a wide range of climates when compared to other fibers sources, making it a practical and environmentally friendly choice for packaging materials. The current research seeks to extract cellulose nanocrystals (CNCs) from hemp fibers using alkali treatment followed by acid hydrolysis and assess their reinforcing capacity in polyvinyl alcohol (PVA) and chitosan (CS) films. AFM analysis confirmed the existence of elongated, uniquely nanosized CNC fibers. The length of the isolated CNCs was approximately 277.76 ± 61 nm, diameter was 6.38 ± 1.27 nm and its aspect ratio was 44.69 ± 11.08. The FTIR and SEM analysis indicated the successful removal of non-cellulosic compounds. Furthermore, the study explored the impact of adding CNCs at varying weight percentages (0, 0.5, 1, 2.5, and 5 wt%) as a strengthening agent on the chemical composition, structure, tensile characteristics, transparency, and water solubility of the bionanocomposite films. Adding CNCs to the CS/PVA film, up to 5 wt%, resulted in an improvement in both the Young's modulus and tensile strength of the bionanocomposite film, which are measured at (412.46 ± 10.49 MPa) and (18.60 ± 3.42 MPa), respectively, in contrast to the control films with values of (202.32 ± 22.50 MPa) and (13.72 ± 2.61 MPa), respectively. The scanning electron microscopy (SEM) images reveal the creation of a CS/PVA/CNC film that appears smooth, with no signs of clumping or clustering. The blending and introduction of CNCs have yielded transparent and biodegradable CS/PVA films. This incorporation has led to a reduction in the gas transmission rate (from 7.013 to 4.159 cm 3 (m 2 day·0.1 MPa)) -1 , a decrease in transparency (from 90.23% to 82.47%), and a lowered water solubility (from 48% to 33%). This study is the inaugural effort to propose the utilization of hemp-derived CNC as a strengthening component in the development of mechanically robust and transparent CS/PVA-CNC bio-nanocomposite films, holding substantial potential for application in the field of food packaging., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The current work describes the synthesis of carbonaceous composites via pyrolysis, based on CMF, extracted from Alfa fibers, and Moroccan clay ghassoul (Gh), for potential use in heavy metal removal from wastewater. Following synthesis, the carbonaceous ghassoul (ca-Gh) material was characterized using X-ray fluorescence (XRF), Scanning Electron Microscopy coupled with Energy Dispersive X-ray (SEM-EDX), zeta-potential and Brunauer-Emmett-Teller (BET). The material was then used as an adsorbent for the removal of cadmium (Cd 2+ ) from aqueous solutions. Studies were conducted into the effect of adsorbent dosage, kinetic time, initial concentration of Cd 2+ , temperature and also pH effect. Thermodynamic and kinetic tests demonstrated that the adsorption equilibrium was attained within 60 min allowing the determination of the adsorption capacity of the studied materials. The investigation of the adsorption kinetics also reveals that all the data could be fit by the pseudo-second-order model. The Langmuir isotherm model might fully describe the adsorption isotherms. The experimental maximum adsorption capacity was found to be 20.6 mg g -1 and 261.9 mg g -1 for Gh and ca-Gh, respectively. The thermodynamic parameters show that the adsorption of Cd 2+ onto the investigated material is spontaneous and endothermic., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In general, during the papermaking process or the production of cellulosic materials for food-packaging applications, lignin and other amorphous components are usually removed via the pulping and multilevel bleaching process to entirely separate them from the fiber. The aim of this work was to study the positive effect that can impart the residual lignin remaining in the alkali-treated fiber surface over bleached fibers to produce an alternative food-packaging cellulosic paper. Herein, cellulosic papers based on alkali-treated and bleached fibers obtained from the Alfa plant were successfully prepared using a compression process. The as-obtained papers were coated by crosslinked starch using a solvent-casting method to improve their mechanical and surface properties. The morphological and contact angle results showed that the residual lignin in the alkali-treated cellulosic papers strongly increased the interfacial adhesion by making the structure denser and more compact, resulting in an improved water resistance property over the bleached ones. On the other hand, it also promoted char formation, slowing down the burning process, resulting in better flame resistance. Additionally, the mechanical properties demonstrated that the presence of lignin contributed to the material rigidity improvement without compromising its flexibility (folding endurance). The as-developed cellulosic papers coated with crosslinked starch could be used for the production of high-quality materials for food-packaging applications using conventional industrial processes., Competing Interests: The authors declare that they have no known competing financial interests. The manuscript has not been published elsewhere and that it has not been submitted simultaneously for publication elsewhere., (This journal is © The Royal Society of Chemistry.)

In search for more effective and eco-friendly adsorbent materials, this study comprehensively investigated Cd 2+ adsorption onto phosphorylated cellulose paper (PCP). For this, cellulose microfibers (CMF) was extracted from Alfa fibers and phosphorylated using the solid-state phosphorylation approach. Then, the prepared PCP samples were characterized by SEM, EDX, XRD, FTIR, TGA, conductometric titration and zeta potential measurement. The adsorption of cadmium ions, the effect of time, pH and Cd 2+ initial concentration were systematically studied in batch experiments. Based on the results, the highest adsorption capacity achieved was 479 mg of Cd 2+ per g of PCP, which was remarkable compared to other modified cellulose capacities cited in the literature. Furthermore, the Cd 2+ removal mechanism was investigated based on characterization results before and after adsorption and also based on the kinetics results. It was concluded that cation exchange and electrostatic attraction between phosphorylated cellulose and the cadmium ion mainly dominated the adsorption process. These findings highlighted that the phosphorylated cellulose paper has a broad application prospect in removal of divalent metal from aquatic solution., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The introduction of phosphate groups into cellulosic fibers allows for the tuning of their fire resistance, chelating and metal-adhesion properties, enabling the development of flame-retardant adhesive and adsorbent materials. Toward that end, the major challenge is developing a novel efficient and environmentally friendly phosphorylation route that offers an alternative to existing methods, which can achieve the targeted properties. For this purpose, cellulosic fibers were chemically modified herein using solid-state phosphorylation with phosphoric acid and urea without causing substantial damage to the fibers. The morphological, physicochemical, structural and thermal characterisations were examined using FQA, SEM, EDX, FTIR, 13 C/ 31 P NMR, conductometric titration, zeta potential measurement and thermogravimetric analysis. All the characterisations converge towards a crosslinked polyanion structure, with about 20 wt% grafted phosphates, a nitrogen content of about 5 wt% and a very high charge density of 6608 mmol kg -1 . Phosphate groups are linked to cellulose through a P-O-C bond in the form of orthophosphate and pyrophosphates. Furthermore, thermal properties of the phosphorylated cellulosic fibers were investigated and a new degradation mechanism was proposed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)