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Highlights This study presents a facile self‐healing electromagnetic interference (EMI) shielding composite by sandwiching a layer of silver nanowires (AgNWs) between two layers of self‐healing polyurethane (SPU). The AgNWs layer forms an interconnected conductive network that effectively reflects and absorbs electromagnetic radiation, providing efficient EMI shielding. The SPU layers contribute autonomous healing of mechanical damages and restoring structural integrity and conductive pathways. The composite films exhibit remarkable EMI shielding effectiveness (SE) (up to 64.6 dB), exceptional mechanical toughness (106.4 MJ/m3), and self‐healing capabilities, outperforming conventional shielding materials. The synergy between AgNWs and SPU layers offers lightweight, flexible, tough, and self‐healing properties, making this material highly promising for applications in wearable electronics, aerospace, and automotive industries where durability and long‐term reliability are critical. Facile fabrication of sandwiched AgNWs layer between SPU films. Sandwiched AgNWs/SPU films with exceptional EMI shielding. AgNWs form conductive networks for efficient EMI shielding. Remarkable mechanical toughness of 106.4 MJ/m3 and self‐healing capability. Potential shielding materials for lightweight, wearable electronics, aerospace. [ABSTRACT FROM AUTHOR]

Flexible electronics require thermally conductive materials with excellent mechanical flexibility to dissipate heat and ensure optimal performance. This work reports the development of metallic ionic cross-linked thermally conductive and mechanically flexible films composed of aramid nanofibers (ANFs) and exfoliated graphene fluoride (EGF) nanosheets. EGF was prepared by liquid exfoliation of fluorinated graphite and incorporated into ANF films fabricated by vacuum filtration. Metallic ion (Al3+) treatment was used to improve interfacial interactions between the EGF fillers and ANF matrix. The EGF-reinforced ANF composite films displayed excellent in-plane thermal conductivity up to 19.48 W/mK for the sample with 50 wt % EGF, owing to the high intrinsic thermal conductivity of EGFs and their preferential alignment along the in-plane direction. The composite films also exhibited outstanding mechanical flexibility and durability, with tensile strength >150 MPa even at 50 wt % EGF content, enabled by efficient stress transfer across the EGF–ANF interface. Thermal conductivity was thermally stable up to 200 °C. The unique combination of high in-plane thermal conductivity, mechanical flexibility, and thermal stability illustrates the potential of ANF/EGF films for effective thermal management in flexible electronics. [ABSTRACT FROM AUTHOR]

In this work, a g-C3N4/porphyrin nanocomposite was fabricated through the self-assembling of monomeric Tetrakis (4-carboxyphenyl) porphyrin (TCPP) molecules with g-C3N4 nanomaterials. The characterizing results showed a good distribution of TCPP nanofibers with a diameter of < 100 nm and several micrometers in length on the g-C3N4 nanoflakes' surfaces. The prepared g-C3N4/porphyrin nanocomposite had two bandgap energies of 2.38 and 2.7 eV, which could harvest a wide range of photon energy in the light spectrum, particularly in visible light. The obtained C3N4/TCPP nanocomposite revealed a remarkable photodegradation efficiency toward rhodamine B dyes, with a RhB removing rate of 3.3 × 10−2 min−1. The plausible mechanism for the photocatalytic performance of the g-C3N4/porphyrin photocatalyst for the RhB dye's degradation was also studied and discussed. [ABSTRACT FROM AUTHOR]

Shape memory polyurethane (SMPU), flexibly cross-linked via a polyethyleneglycol (PEG) spacer attached to its side through an allophanate group, was tested for shape memory and compared with a linear SMPU. The new SMPU was composed of 4,4'-methylenebis(phenylisocyanate) (MDI), poly(tetramethyleneglycol) (PTMG-2000), and 1,4-butanediol (BD), and included polyethyleneglycol (PEG-200) as a spacer. A second MDI, linked to the carbamate group of the first MDI, served as the connecting point for the PEG-200. Two types of SMPU, differing according to their soft segment (PTMG-2000) and linker (PEG-200) contents, were compared in mechanical and shape memory properties. In the best case, a 780% increase in maximum stress was attained without any sacrifice in strain for the new material compared with the linear polymer. In particular, the stress-strain curve showed that the PEG-crosslinked SMPU had superior tensile mechanical properties. Its shape recovery was as high as 99%, which is the best value we have measured for an SMPU. After four cyclic tests, shape recovery remained greater than 95%. Shape retention of the best SMPU remained above 93% even after four cyclic tests. Here, results demonstrating the extraordinary shape memory properties of these types of SMPU, together with differential scanning calorimetry (DSC) and infrared spectroscopy data, are analyzed and discussed. POLYM. ENG. SCI., 50:2457-2466, 2010. [C] 2010 Society of Plastics Engineers, INTRODUCTION Shape memory polymers (SMP), including shape memory polyurethane (SMPU), have been extensively studied due to their unparalleled properties. They have practical and adjustable phase transition temperature ranges, high and [...]

We developed a liquid crystal (LC) aptamer biosensor for the sensitive detection of amoxicillin (AMX). The AMX aptamer was immobilized onto the surface of a glass slide modified with a mixed self-assembled layer of dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DMOAP) and (3-aminopropyl) triethoxysilane (APTES). The long alkyl chains of DMOAP maintained the LC molecules in a homeotropic orientation and induced a dark optical appearance under a polarized light microscope (POM). In the presence of AMX, the specific binding of the aptamer and AMX molecules induced a conformational change in the aptamers, leading to the disruption of the homeotropic orientation of LCs, resulting in a bright optical appearance. The developed aptasensor showed high specificity and a low detection limit of 3.5 nM. Moreover, the potential application of the developed aptasensor for the detection of AMX in environmental samples was also demonstrated. Therefore, the proposed aptasensor is a promising platform for simple, rapid, and label-free monitoring of AMX in an actual water environment with high selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

An irreversible thermochromic material based on manganese violet (MnNH4P2O7) is synthesized. The crystal phase, chemical composition, and morphology of the synthesized material are analyzed using X-ray diffraction, scanning electron microscopy coupled with energy-dispersive X-ray spectrometry, and Fourier-transform infrared spectroscopy. The absorption spectra of the synthesized material are obtained using a UV-Vis spectrometer, and the thermochromism exhibited by the powdered samples at high temperatures is also investigated. The as-synthesized manganese violet pigment consists of pure α-MnNH4P2O7 phase. In addition, the synthesized pigment largely consists of hexagonal crystals with a diameter of hundreds of nanometers. On heating, the pigment simultaneously loses H2O and NH3 in two successive steps at approximately 330–434.4 °C and 434.4–527 °C, which correspond to the formation of an intermediate phase and of Mn2P4O12, respectively. An overall mass loss of 14.22% is observed, which is consistent with the expected 13.79%. An irreversible color change from violet to white is observed after exposure of the synthesized manganese violet pigment at 400 °C for 30 min. This is attributed to the oxidation of ammonia to hydroxylamine, which then decomposes to nitrogen and water, or alternatively to the direct oxidation of ammonia to nitrogen. Furthermore, we demonstrate the potential application of synthesized manganese violet in the production of irreversible thermochromic paint by mixing with potassium silicate solution as a binder and deionized water as a solvent at a specific ratio. The thermochromic paint is then applied in fabrication of irreversible thermochromic sensors by coating it onto a steel plate surface. Finally, we show that manganese violet-based irreversible thermochromic sensors are able to detect temperatures around 400 °C by changing color from violet to white/milky. [ABSTRACT FROM AUTHOR]

Graphene-based aerogels are among the lightest materials in the world and have been extensively studied for environmental remediation. In this work, an Fe 3 O 4 /graphene aerogel material was synthesized using the co-precipitation method. The prepared material was characterized using X-ray diffraction (XRD), scanning electron microscopy/X-ray energy dispersive spectroscopy (FESEM/EDX), infrared spectroscopy (FT-IR), and vibration sample magnetization (VSM). The results showed that the Fe 3 O 4 nanoparticles with a particle size of less than 100 nm were well-distributed on the surface of the graphene aerogel. The prepared Fe 3 O 4 /graphene aerogel showed effective removal of 2,4-D herbicide from the aqueous solution with a maximal adsorption capacity of approximately 42.918 mg g -1 . The adsorption isotherms and kinetics were investigated to study the adsorption behaviour of the resultant material. The saturation magnetism value of the aerogel was determined to be about 20.66 emu g -1 , indicating that the adsorbent could be easily collected from the solution using an external magnet. These results implied that the prepared Fe 3 O 4 /graphene aerogel could be a promising adsorbent for the removal of 2,4-D herbicide from water., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An inorganic thermochromic material based on Cr-doped Al₂O₃ is synthesized using a solid-state method. The crystal structure, chemical composition, and morphology of the synthesized material are analyzed using X-ray diffraction, scanning electron microscopy coupled with an energy-dispersive X-ray spectrometer, and Fourier transform infrared (FT-IR) spectroscopy. The color performances of the synthesized material are analyzed using a UV-VIS spectrometer. Finally, the thermochromism exhibited by the powdered samples at high temperatures is investigated. The material exhibits exceptional thermochromic property, transitioning from pink to gray or green in a temperature range of 25-600 °C. The change in color is reversible and is dependent on the surrounding temperature and chromium concentration; however, it is independent of the exposure time. This novel property of Cr-doped Al₂O₃ can be potentially employed in reversible thermochromic sensors that could be used not only for warning users of damage due to overheating when the environmental temperature exceeds certain limits, but also for detecting and monitoring the temperature of various devices, such as aeronautical engine components, hotplates, and furnaces., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.