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Superhydrophobic coatings have been used to solve the problems of oil spills polluting water sources and water resource shortages. However, the short service life of superhydrophobic coatings limit their widely application. In this work, a novel fluorine‐free, self‐healing, and superhydrophobic coating composing of polydimethylsiloxane (PDMS), polydopamine (PDA) modified halloysite nanotubes (HNT), and beeswax (BW) are fabricated for oil/water separation as well as fog‐water collection. Herein, PDA stabilizes the dispersion of HNT in the coating, and meanwhile enhances the adhesion of modified nanoparticles on fabric surfaces. The as‐fabricated coatings occupied a water contact angle of 163.1°, demonstrating exceptional superhydrophobic characteristics. The superhydrophobic coating exhibited superior oil/water separation efficiency of over 99.5% and outstanding fog‐water collection rate of 990 ~ 1208 mg cm−2 h−1. Owing to the presence of BW, the coatings demonstrated remarkable self‐healing properties and can regain superhydrophobicity after 100 wear cycles with just a short heating treatment. Therefore, this facile strategy has great potential for large‐scale manufacturing of multifunctional superhydrophobic coatings. [ABSTRACT FROM AUTHOR]

The urgent problem to solve is how to design a kind of green and porous adsorbent that can effectively remove dye pollutants in the field of the sewage treatment. The objectives of this investigation are to incorporate zeolitic imidazolate frameworks‐8 (ZIF‐8) particles in situ onto the surface of multiwalled carbon tubes (MWCNTs) and integrate them into an agarose‐sodium alginate (ASA) double network hydrogel. The resulting composite hydrogel beads, denoted as MWCNTs/ZIF‐8/ASA (MZASA), are synthesized using calcium ion crosslinking. The addition of agarose is employed to create a dual‐crosslinked hydrogel, thereby enhancing the mechanical properties of the ASA hydrogel. By incorporating MWCNTs/ZIF‐8 nanoparticles, the surface area of the MZASA hydrogel is augmented, leading to an enhancement in dye adsorption capacity. In batch sorption mode, the maximum absorbency of the resulting hydrogel beads for methylene blue (MB) is 493.799 mg/g, which was a third greater than that of pure SA beads. Absorption of MB obeys the pseudo‐second‐order kinetic model and Langmuir isotherm model, suggesting monolayer chemisorption adsorption. Analysis of the thermodynamics proves that the entire adsorption process is exothermic and spontaneous. Moreover, the MZASA hydrogel beads show high selectivity for cationic dyes in the mixed dye test. Hence, the synthesized MZASA hydrogel beads serve as a highly effective, innovative, and reusable adsorbent for eliminating cationic dyes from water‐based solutions. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF) has been extensively used in the research of microwave absorption owning to its excellent performance, but it also faces a series of problems such as impedance mismatch and low absorption intensity. The core‐sheath microstructure with CF as the inner core is constructed to solve the above issues by the introduction of other sheath layers. In this work, the MoS2 sheath and polyaniline (PANI) sheath are successively introduced into the CF matrix to obtain a hierarchical CF@MoS2@PANI nanocomposite with core‐sheath structure through a straightforward hydrothermal method and in‐situ polymerization. The obtained CF@MoS2@PANI nanocomposite exhibit the minimum reflection loss value of −42.23 dB at 10.11 GHz while the thickness is 2.5 mm, much higher than those of pure CF (below −10 dB) and CF@MoS2 nanocomposite (−25.60 dB). Moreover, the distinctive hierarchical core‐sheath structure contributes to providing more active sites, prolonging the transmission path of electromagnetic waves, and forming heterogeneous interfaces. Consequently, the electromagnetic wave attenuation mechanism of CF@MoS2@PANI nanocomposite is attributed to a synergistic effect of conductive loss, multiple reflection/scattering, dipole polarization, and interface polarization. This work offers an effective and promising strategy to design a three‐dimensional hierarchical core‐sheath microstructure for the development of composite absorbers. [ABSTRACT FROM AUTHOR]

When hydrogels are in environments with high water content, they usually undergo swelling, leading to a degradation of mechanical properties, which severely limits their application in underwater sensing. To solve this problem, we synthesized an anti-swelling, tough, double-crosslinked, dual-network hydrogel, P(AA-SMA)-CMC-Na, for underwater sensing. Due to the hydrophobic association and electrostatic interactions between the cationic surfactant N-Hexadecyltrimethylammonium chloride (CTAC) and poly (acrylate-methacrylate octadecyl ester) [P(AA-SMA)], as well as the dense network structure brought about by double cross-linking and the incorporation of CMC-Na, the hydrogel has excellent anti-swelling properties and mechanical properties (large stretchability of 955%, tensile strength of 252 kPa). Notably, after seven days of immersion in water (pH = 3, 5) and saline, stress and strain were elevated compared to the original hydrogel (strain up to 1460% and stress up to 805 kPa after immersion). The dynamic hydrophobic association of CTAC with SMA and the large number of hydrogen bonds within the hydrogel contributed to the excellent self-healing efficiency of the hydrogel (90%). The hydrogel was fabricated into a flexible strain sensor that showed keen sensitivity in the sensing range of 0–400% (GF values of 1.55, 2.87, and 5.03 for the ranges of 0–200%, 200–300% and 300–400%, respectively). It could accurately detect real-time signals of human movement in air, underwater, and seawater. Therefore, the P(AA-SMA)-CMC-Na hydrogel can meet the needs of underwater sensing and have great potential for applications in electronic skin, personal health detection, and flexible wearable electronics. [ABSTRACT FROM AUTHOR]

A multifunctional hydrogel (C‐ASI‐G) was prepared through a simple acid–base neutralization method. Due to the large number of electrostatic cross‐linked network in the hydrogel and the reversible network, the hydrogel showed good mechanical properties (stress is 495 kPa, strain is 772%) and excellent self‐healing performance (self‐healing efficiency is over 95%). In addition, by adding glycerin to the dispersion medium, hydrogel retain water for a long time and remain flexible at low temperature. The hydrogel contains an ionizable polymer electrolyte, sodium polystyrene sulfonate, so it has outstanding electrical conductivity (0.36 s/m). The hydrogel can be used in general strain sensing and temperature sensing, its conductivity changes with temperature. The temperature and conductivity of the hydrogel were simulated as function, the environmental temperature of the hydrogel could be calculated by the conductivity of the hydrogel, and the error was less than 0.45°C. Because hydrogel can sense stress and temperature stimuli through the change of electrical signals, it will exhibit broad application prospect in the field of bionic intelligent robots. [ABSTRACT FROM AUTHOR]

In this work, the CO0.5Ni0.5Fe2O4 nanoparticles modified by phosphoric acid and NCO groups were prepared as flame‐retardants and cross‐linking centers. After modification, the dispersibility and flame‐retardant properties of the nanoparticles were effectively improved. On this basis, a kind of two‐component polyester‐based anti‐smudge and flame retardant hybrid coating in situ polymerization was prepared by using dihydroxy mono‐terminated PDMS to provide low surface energy, dipentaerythritol (Di‐PE) as a charring agent to provide sufficient cross‐linking sites. Water, ink, pump oil, and cooking oil could slide off the coated surface without leaving any traces. These novel hybrid coatings exhibit excellent anti‐graffiti properties and corrosion resistance even with 2 wt% PDMS and 3 wt% modified nanoparticles content. Moreover, Si, P, and CO0.5Ni0.5Fe2O4 all resulted in the formation of a char protective layer during burning. The thermal properties and flame retardant properties of the hybrid coatings were significantly improved. The peak heat release rate (PHRR) curves and the smoke production rate (PSPR) of hybrid coatings (3 wt% modified CO0.5Ni0.5Fe2O4) decreased by 44.2%, 55.7%, respectively, compared with pure composites. Besides, the hybrid coatings can be applied to a variety of substrates, including glass, steel, and fabric. [ABSTRACT FROM AUTHOR]

Heavy metal Pb2+ pollutants have become an important environmental problem, which threatens public health and ecosystems worldwide. In this study, to explore the effective treatment of trace Pb2+ pollution in water, molecular dynamics simulation combined with DFT calculations was used to study the transportation behavior of Pb2+ using polygonal carbon nanotubes (PCNT: P = 4, 5, 6, 8)/graphene composites (PCNTs/G). It is shown that due to the confinement effect of PCNTs, both H2O and H3O+ can form a hydrogen-bonding network and transport them in the form of proton exchange through the PCNT channels. The trajectory shows that with the help of a hydrogen-bonding network, the probability of Pb2+ passing through the 8N channel is enhanced. Then, upon the fluorine modification of PCNTs, mutual effects of both the hydrogen-bonding network and electrophilic attraction make Pb2+ get through the channel of 8F. It is indicated that with respect to 4CNT/G, 5CNT/G, and 6CNT/G, 8CNT/G is not accurate for Pb2+ interception at the outlets. In addition, the RDF, and HOMO–LUMO orbitals indicate that the affinity from the hydrogen-bonding network and PCNT walls both play important roles in particle transportation. This work can not only provide a basic understanding of Pb2+ transportation in PCNTs from the perspective of diffusion but also be helpful to guide the strategy on how to deal with Pb2+ pollution in waters. [ABSTRACT FROM AUTHOR]

Successfully designed and synthesized PS@Ni@Cu core–shell composite microspheres, which provide efficient electronic transmission for anisotropic conductive films for electronic packaging applications. Herein, a simple method for preparing core–shell composite microspheres using Pickering emulsion polymerization as a template, a dense nano‐nickel shell layer was coated on the surface of polystyrene to obtain PS@Ni microspheres, the microspheres have conductivity and magnetic properties. Then the microspheres were coated with nano‐copper layer by electroless plating to enhance the mobility of electrons in specific media. Finally, the microspheres are laminated in epoxy resin, which can realize directional (horizontal, inclined, and vertical) movement under magnetic field force to form anisotropic conductive film. The conductivity is 171.68 S cm−1, the adhesiveness and conductivity of the film can be changed by adjusting the content of microspheres. The film has excellent thermal stability, good adhesion, and can be anisotropic conductive. The difference in conductivity between the conductive direction and the insulating direction is about 108 orders of magnitude, and it can adapt to strong acids and alkalis and other more extreme environments. It is significance to the development of electronic packaging and is expected to be widely used in the field of electronic devices. [ABSTRACT FROM AUTHOR]

In this paper, PVA/PAA‐PAM‐IS/GC composite hydrogels are prepared using polyvinyl alcohol (PVA), poly acrylic acid (PAA), poly acrylamide (PAM), and iron sulfate hydrate (IS) glycerol (GC). The crosslinking network is formed by the coordination of carboxyl groups with ions, which forms PVA with semi‐interpenetrating network. The mechanical properties and self‐healing properties of PVA/PAA‐PAM‐IS/GC composite hydrogels are excellent. The stress, strain and self‐healing efficiency of PVA/PAA‐PAM‐IS/GC composite hydrogels can reach 840 kPa, 784%, and above 95%, respectively. The antifreeze and water retention properties of PVA/PAA‐PAM‐IS/GC composite hydrogels are improved by glycerol. PVA/PAA‐PAM‐IS/GC composite hydrogels remains flexible at low temperatures and moist for a long time at room temperature. The conductivity of the hydrogel increases with the increase of temperature because the interactions between glycerol, water molecules and ammonium ions are affected by the temperature, the multifunctional conductive hydrogel can be used in strain sensing and temperature sensing. In summary, PVA/PAA‐PAM‐IS/GC composite hydrogels can provide a guide in the field of electronic intelligence. [ABSTRACT FROM AUTHOR]

In this paper, a kind of fluorescent anti-counter feiting acrylate pressure-sensitive adhesive (PSA) label was prepared using 7-hydroxycoumarin and acrylate monomer. First,7-hydroxycoumarin was reacted with 3-bromopropylene and coumarin derivatives were prepared. And thio-terminated intermediate-mercaptan A was obtained by the reaction of the mercaptan group of 2,2ʹ-(Ethylenedioxy) diethanethiol with the double bond. Then, mercaptan A was reacted with acrylate and a novel fluorescent anti-counterfeiting acrylate PSA was prepared. Finally, a novel fluorescent anti-counterfeiting acrylate PSA label was prepared by coating the adhesive on the PET label. The experimental results showed that with the increasing of mercaptan A content, the tensile strength, shear resistance, thermal stability property and fluorescence of mercaptan A-acrylate PSA were improved. When the content of mercaptan A was 5 wt %, the tack,180° peel strength and shear resistance of mercaptan A-acrylate PSA were No.5 ball, 0.54 KN/m and 87 h, respectively. The mercaptan A-acrylate PSA showed bright blue fluorescence under the ultraviolet lamp. [ABSTRACT FROM AUTHOR]

Excessive CO2 emission has caused severe greenhouse problems. CO2 reduction reaction (CO2RR) is considered to be a promising strategy to effectively reduce CO2 emission, which not only captures CO2 in large quantity, but also produces high value-added chemicals. Herein, CO2RR on the CuPc/graphene single-atomic catalyst has been studied via density functional theory (DFT) calculations. It shows that CO2 is inclined to convert to CH3OH, followed by HCOOH and CH4. The most favored pathway to produce CH3OH is *CO2 → *COOH → *CO → *CHO → *OCH2 → *OCH3 → *OHCH3, for which the potential-limiting step is *CO2 → *COOH (endothermic by 1.41 eV). Both density of states and differential charge further indicate the high reactivity of single atomic Cu, and uncover the effect of electrostatic interaction on the hydrogenation pathway. This study can provide an insight into the structure–reaction relationship for CO2RR on CuPc/graphene, and help guide the design of highly effective catalysts. [ABSTRACT FROM AUTHOR]