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A thermal conductive structural adhesive (TCSA) plays a crucial role in battery performance and safety. TCSA made of polyurethane (PU) has not only a good thermal conductivity but also good mechanical strength and substrate bonding strength. However, it has to be cost‐effective and easy to be prepared. This work aims to synthesize a series of castor oil‐based PU TCSAs with different amounts of thermal conductive powder using commercially available castor oil polyols, isocyanates, Al2O3, and additives. The shear strength of the TCSA containing 88% thermally conductivity powder reached 5.6 MPa, which was similar to that without the thermal conductivity fillers, but its toughness significantly decreased. Its thermal conductivity was as high as 1.8 W/mK, and it was thermally stable below 270°C. [ABSTRACT FROM AUTHOR]

Cleanup of oil spills has become one of the most challenging tasks in recent years, as marine oil spills have had a great negative impact on human health and the ecological environment. This also urgently requires the development of new materials and methods with superhydrophobic properties for oil–water separation. As new porous materials, metal–organic frameworks (MOFs) have attracted much attention due to their unique structures and fascinating properties. However, powdered MOF materials are difficult to recycle, and therefore, suitable substrates need to be selected to construct superhydrophobic composites. The surface hydroxyl groups of cellulose fibers offer great possibilities for their superhydrophobic preparation. In this paper, HDTMS‐UiO‐66@CFs composites with superhydrophobicity were strategically synthesized by in‐situ growth of Zr(IV)‐based MOFs linked to hexadecyltrimethoxysilane (HDTMS) on cellulosic fibers (cotton fabric) by using a hydrothermal synthesis method. The HDTMS‐UiO‐66@CFs composites have a water contact angle of 172° and the absorption capacity of light oil and heavy oil is more than 1100%, and the oil–water separation efficiency is as high as 96%. Due to the in‐situ growth of the HDTMS‐UiO‐66 material on cotton fibers, which makes the material more resistant and stable, the material can still maintain its superhydrophobic properties in various harsh environments and after repeated use. Therefore, the newly developed HDTMS‐UiO‐66@CFs composites have a high potential as novel adsorbent materials for cleaning up offshore oil spills and other applications. Highlights: In‐situ growth of superhydrophobic metal‐organic frameworks (MOF) particles on cellulose fibers.The porous structure of hexadecyltrimethoxysilane (HDTMS)‐UiO66 plays a key role in hydrophobicity.HDTMS‐UiO66@CFs are chemically stable and have long‐term durability. [ABSTRACT FROM AUTHOR]

BiVO4 is one of the most promising photoanode materials for photoelectrochemical (PEC) solar energy conversion, but it still suffers from poor photocurrent density due to insufficient light‐harvesting efficiency (LHE), weak photogenerated charge separation efficiency (ΦSep), and low water oxidation efficiency (ΦOX). Herein, we tackle these challenges of the BiVO4 photoanodes using systematic engineering, including catalysis engineering, bandgap engineering, and morphology engineering. In particular, we deposit a NiCoOx layer onto the BiVO4 photoanode as the oxygen evolution catalyst to enhance the ΦOX of Fe‐g‐C3N4/BiVO4 for PEC water oxidation, and incorporate Fe‐doped graphite‐phase C3N4 (Fe‐g‐C3N4) into the BiVO4 photoanode to optimize the bandgap and surface areas to subsequently expand the light absorption range of the photoanode from 530 to 690 nm, increase the LHE and ΦSep, and further improve the oxygen evolution reaction activity of the NiCoOx catalytic layer. Consequently, the maximum photocurrent density of the as‐prepared NiCoOx/Fe‐g‐C3N4/BiVO4 is remarkably boosted from 4.6 to 7.4 mA cm−2. This work suggests that the proposed systematic engineering strategy is exceptionally promising for improving LHE, ΦSep, and ΦOX of BiVO4‐based photoanodes, which will substantially benefit the design, preparation, and large‐scale application of next‐generation high‐performance photoanodes. [ABSTRACT FROM AUTHOR]

The notorious lithium polysulfides (LiPSs) shuttle effect, which results in low capacity, subpar rate performance, and quick capacity deterioration, has severely restricted the practical applications of lithium sulfur (Li‐S) batteries. Therefore, it is very important for modified materials to promote thermodynamics and redox kinetics in the entrapping‐conversion process of polysulfides. Density functional theory (DFT) calculations show that ferric group (Fe, Co, Ni) transition metals not only provide moderate binding contacts with LiPSs but also act as an active catalyst in the spontaneous and sequential lithiation of S8 to Li2S by d‐band energy level splitting, and quick migration of Li ions can be operated on their surface, enhancing the utilization of LiPSs. Experimentally, felicitously‐fabricated ferric group (Fe, Co, Ni) transition metals encapsulated in nitrogen‐doped carbon nanotubes (M@NCNT) electrocatalysts were introduced into Li‐S batteries via separator functionalization. Actually, the experiments demonstrated that the excellent shuttle effect hindering was enabled. Consistent with theoretical predictions, Li‐S batteries with Ni@NCNT modified separators had significantly improved rate capacity and cycling stability. The cells with Ni@NCNT were able to achieve a high initial discharge capacity of 1035 mAh g−1 and a capacity retention rate of 70% at 500 discharges at 1.0 C with a 0.060% capacity decay each cycle, performing considerable cycle‐life with state‐of‐the‐art separators. Our work demonstrated a realistic separator‐modified strategy of d‐band energy level splitting from ferric group metals for high‐performance and long‐life Li‐S batteries, further propelling Li‐S battery commercialization. [ABSTRACT FROM AUTHOR]

With the development of science and technology and electronic industry, electromagnetic wave pollution has become the fifth largest pollution in the world today, so it is very important to develop a material with good wave absorbing properties. In this study, polyaniline was loaded onto the surface of carbon nanotubes (CNTs) bundles in Buckypaper by electropolymerization, and epoxy resin was used as the matrix to prepare a polyaniline (PANI)/Buckypaper/EP composite absorber with integrated structure and function. The research shows that the CNTs are prepared into Buckypaper with a three‐dimensional porous structure by vacuum filtration. This three‐dimensional porous structure ensures that CNTs can be added at a high content and uniformly dispersed in epoxy resin. PANI adjusts the impedance matching of Buckypaper and adds more loss mechanisms. Under the optimal matching thickness of 1.5 mm, the optimal reflection loss reaches −29.31 dB, and the absorption bandwidth is 3.12 GHz. At the same time, the interaction between the π–π noncovalent bond of PANI and the delocalized π electrons on the surface of CNTs improves the mechanical strength of Buckypaper. The tensile strength reached 42.17 MPa, an increase of 92.82% compared with pure BP/EP. The research in this article is expected to provide a feasible idea for the preparation of structure–function integrated materials. [ABSTRACT FROM AUTHOR]

Long chain branched polypropylene/clay‐supported calcium pimelate (LCBPP/CaHA‐OMMT) composites and their foams were prepared using self‐made CaHA‐OMMTs. The CaHA‐OMMT showed high β‐nucleation efficiency, especially that with larger initial interlayer distance could induce 89% of β crystal in LCBPP with a dosage of 0.5%. Clay layers were mostly exfoliated in the composites with low CaHA‐OMMT content, while intercalated structure was dominant and agglomeration occurred when the content of CaHA‐OMMT was higher than 2%. The composite foams were prepared with improved compression molding. The cell structure of the composite foams is improved, that is, the density, cell size, and cell size distribution decreased, and the cell density increased compared with that of LCBPP foam. The minimum average cell size of LCBPP/CaHA‐OMMT foams was 77 μm and the maximum cell density was 2.8 × 106 cells/cm3 with the CaHA‐OMMT content of 2%. It is concluded that there are two requirements for high nucleation efficiency: the CaHA was supported on OMMT layers, and the OMMT platelets were dispersed well and exfoliated. The compression properties of the composite foams, including compression modulus, energy absorption density and failure strength increased first and then decreased with the increase of CaHA‐OMMT content. [ABSTRACT FROM AUTHOR]

Metal phosphates have been widely explored in lithium ion batteries and sodium ion batteries owing to high theoretical capacities, mild toxicity and low cost. However, their potassium ion battery applications are less reported due to the limited conductivity and the slow diffusion kinetics. Considering these drawbacks, novel structured M2P2O7/C (M=Fe, Co, Ni) nanoflake composites are prepared through an organic‐phosphors precursor‐assisted solvothermal method and a subsequent high temperature annealing process. The designed Co2P2O7/C composite exhibits the highest rate capacity with 502 mAh g−1 at 0.1 A g−1 and good cyclability for 900 cycles at 1 A g−1 and 2 A g−1 when compared with Ni and Fe based composites. The superior electrochemical performance can be attributed to their unique nanoparticle‐assembled nanoflake structure, which can afford enough active sites for K+ intercalation. In addition, the robust pyrophosphate crystal structure and the in situ formed carbon composition also have positive effects on enhancing the long‐term cycling performance and the electrode's conductivity. Finally, this organic‐phosphors precursor induced simple approach can be applied for easy fabrication of other pyrophosphate/carbon hybrids as advanced electrodes. [ABSTRACT FROM AUTHOR]

Copper‐doped ZnS/ZnO (CSO) hexahedrons in egg tart‐like morphology were fabricated by an in‐situ synthetic strategy to promote photocatalytic hydrogen (H2) production. Hexahedral CuO/ZnO precursors in micro sizes were prepared by a solvothermal method. A subsequent moderate sulfurization of the precursor led to the formation of ZnS/ZnO heterostructures without alteration of the hexahedral morphology. In addition, the in‐situ methodology ensured the homogeneous doping of copper species with ZnS/ZnO heterostructures, which significantly improved the electric conductivity of these hybrid materials. Because of the structural and compositional features of the hybrid materials, a maximum H2 production rate of 1.044 mmol g−1 h−1 with high recycling stability (even after 12 h) has been delivered based on an interfacial catalysis. Thus, this study may provide an efficient strategy to optimize the physical and chemical properties of photocatalysts in microsize scale. [ABSTRACT FROM AUTHOR]

Poly(3‐hydroxybutyrate) (PHB), a renewable feedstock from microorganisms, was a good resource for propylene production by a simple one‐pot reaction. The reaction was catalyzed by triruthenium dodecacarbonyl (TD) at relatively mild temperature (240 °C), and the yield and selectivity of propylene reached 22.9 wt% and 46.8%, respectively. A small part of hydrocarbon oils reached 9 wt% was also obtained, which contained 79.1 wt% of carbon and 12.3 wt% of hydrogen, with a theoretical high heating value of 41.2 MJ/kg. Poly(3‐hydroxybutyrate), a renewable biofeedstock accumulated in many bacteria, has been converted to propylene and oils in a simple one‐step reaction at relatively mild reaction condition (i.e., 240 °C, for 6 h), in the presence of triruthenium dodecacarbonyl catalyst. The yield of propylene and oils were 22.9 wt% and 9 wt%, respectively, and the oils had a theoretical high heating value of 41.2 MJ/kg. [ABSTRACT FROM AUTHOR]

Thermally induced shape memory polymers (SMPs) are fragile and brittle when cooling to a low temperature to generate temporary shapes. In the present study, the authors implement a new design strategy for fabricating elastomeric SMPs with low‐temperature flexibility by engineering reversible sacrificial hydrogen bonds into a chemically crosslinked network. Compatible, amorphous, hindered phenol moieties (Irganox 1010) are incorporated into epoxidized natural rubber (ENR) and the ENR composites are cured with zinc diacrylate (ZDA). Such reversible sacrificial bonds can rupture prior to the rupture of the bonds of the crosslinked network during stretching, which will dissipate energy and facilitate reorientation of the rubber chains. Based on the functional mechanisms, ENR composites exhibit unusual toughness and flexibility and can undergo large deformations even when below their Tg. Irganox 1010 can also be used to tune the glass transition temperature (Tg) and improve the chain mobility of the elastomer sample by providing sufficient intermolecular hydrogen bonding interactions. ENR composites demonstrate thermally triggered shape memory performance. Moreover, the dissociation/reformation of hydrogen bonds upon stretching/cooling can endow the elastomer sample with unique reversible plastics shape memory (RPSM) performance. These SMPs possess excellent shape fixity and recovery. [ABSTRACT FROM AUTHOR]

ABSTRACT Improvement of mechanical and thermal properties is always the goal of high-performance general plastic for engineering applications. Herein, isotactic polypropylene/glass fiber/tetrapod-shaped zinc oxide (iPP/GF/T-ZnOw) composites are developed via melt-extrusion on twin-screw extruder. To improve the distribution of T-ZnOw in iPP matrix, T-ZnOw is first modified by various silane coupling agents and its structure is characterized by scanning electron microscopy, Fourier transform infrared spectra, and X-ray diffraction (XRD). The optimized treatment condition is determined via comparison of activation index. The introduction of GF and T-ZnOw could improve the mechanical properties including tensile strength, elastic modulus, flexural strength, flexural modulus, and impact strength, indicating that the surface modification and compatibilizer could enhance the interfacial interaction of iPP/GF/T-ZnOw composites. Moreover, XRD and differential scanning calorimentryresults show that T-ZnOw as a novel β-nucleating agent could induce the formation of β-crystal and the existence of GF counteracts the formation of β-crystal induced by T-ZnOw. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44217. [ABSTRACT FROM AUTHOR]

A novel monomer called 1,1'-ferrocenediacyl anilide (FcA) was synthesized from ferrocene (Fc). Copolymerization was carried out between FcA and aniline (ANI) by an electrochemical method. The novel monomer and copolymer were characterized with ¹H-NMR, Fourier transform infrared (FTIR) spectroscopy, and ultraviolet--visible (UV-vis) spectroscopy. The hydrogen protons of the benzene ring were moved to a low field in ¹H-NMR, and the absorption band of N=Q=N (where Q is the quinoid ring) appeared in the FTIR spectrum of the polymer. The peaks of both Fc and the π-π* electronic transition in the UV-vis spectra were redshifted. The results indicate that the copolymer mainly existed as a highly delocalized conjugated system. X-ray diffraction analysis established further proof, and the process of electrochemical deposition was observed by scanning electron microscopy. The optimal synthesis conditions of the copolymer were determined through changes in the monomer molar ratios and the scan rate. The ideal performance of the copolymer was gained when the monomer molar ratio between FcA and ANI was 1:4 and the scan rate was 50 mV/s. Furthermore, the electrochemical performances were tested in detail by cyclic voltammetry, galvanostatic charge--discharge testing, and electrochemical impedance spectroscopy. The results show that the specific capacitance of poly(1,1'-ferrocenediacyl anilideco-aniline) increased up to 433.1 F/g at 0.5 A/g, the diffusion resistance was very small, and the durability was good enough. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel flame-retardant synergist, chitosan/urea compound based phosphonic acid melamine salt (HUMCS), was synthesized and characterized by Fourier transform infrared spectroscopy and 31P-NMR. Subsequently, HUMCS was added to a fire-retardant polypropylene (PP) compound containing an intumescent flame-retardant (IFR) system to improve its flame-retardant properties. The PP/IFR/HUMCS composites were characterized by limiting oxygen index (LOI) tests, vertical burning tests (UL-94 tests), microscale combustion calorimetry tests, and thermogravimetric analysis to study the combustion behavior and thermal stability. The addition of 3 wt % HUMCS increased the LOI from 31.4 to 33.0. The addition of HUMCS at a low additive amount reduced the peak heat-release rate, total heat release, and heat-release capacity obviously. Furthermore, scanning electron micrographs of char residues revealed that HUMCS could prevent the IFR-PP composites from forming a dense and compact multicell char, which could effectively protect the substrate material from combusting. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40845. [ABSTRACT FROM AUTHOR]

Starch/EVA (ethylene-vinyl acetate copolymer)/modified kaolin nanocomposite foaming materials were prepared. The modified kaolin was obtained by γ-methylacryloyl oxypropyl trimethoxysilane (silane coupling agent KH-570) as the nucleating agent. The effects of the modified kaolin were analyzed by activation index, and the structure was characterized by Fourier transform infrared (FT-IR) and SEM. The effects of modified kaolin on the mechanical properties and the cellular structure of the composite foams were also studied. According to the results, when 1.8 phr (parts per hundert parts of resin) silane coupling agent KH-570 modified kaolin, the activation index was 100%. It was found that the modified kaolin played an important role in the formation of the microstructure and the mechanical properties of the composites foams. Modified kaolin could increase the amount of the cells and reduce cell size significantly. The optimum tearing strength of the composite foams was 12.78 kg/cm with 20 phr modified kaolin added. The results were attributed to the nucleation effect of the modified kaolin particles, the high melt viscosity and the complex interface interactions between EVA chains and kaolin particles. [ABSTRACT FROM AUTHOR]

A novolac like phenolic resin was prepared by copolymerization with phenol and hydrolyzed starch as the substitute for formaldehyde under catalysis of sulfuric acid. Liquefied phenolated lignosulfonate was introduced to the phenol-starch resin in this study as a partial phenol substitute. The phenol-formaldehyde resin, phenol-starch resin, and lignin-phenol-starch resin were characterized with lab standard analysis for their physicochemical specifications such as solid content, gel time, softening point, viscosity, and free phenol content according to corresponding Chinese National Standards. Mechanical properties of modified and unmodified resin core sand were investigated. Structures of modified and unmodified resins were characterized with infrared spectrum analysis (FTIR) and carbon-13 NMR spectrometry (13C NMR), while their thermal properties were studied with thermogravimetric analysis (TGA) and DSC. The modified resin and its core sand have acceptable physicochemical specifications, thermal resistance and mechanical properties as compared with unmodified resin and phenol-formaldehyde resin. [ABSTRACT FROM AUTHOR]

Polyaniline/MnO2/graphite felt (PMGF) composite, which can be used as a novel free-standing, flexible electrode for supercapacitors, was fabricated via a facile electrochemical method. Polyaniline/graphite felt (PANI/GF) electrode was prepared by electropolymerization of PANI onto the GF. Subsequently, manganese dioxide (MnO2) was electrodeposited on the surface of the PANI/GF electrode to prepare PMGF electrode. The microstructure and morphology of the as-prepared samples were characterized by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Specific surface area was examined using N2 adsorption/desorption test. Cyclic voltammogram, chronopotentiometry techniques and electrochemical impedance spectroscopy were introduced to investigate the electrochemical performance of the composites. The PMGF electrode exhibited specific capacitance as high as about 630 F g−1 at the current density of 0.5 A g−1, which is much higher than that of PANI/MnO2 composites reported previously. The high specific capacitance of PMGF may be attributed to the fact that the porous GF is a good conductive matrix for the dispersion of PANI/MnO2 and it can facilitate easy access of electrolytes to the electrode, which results in enhancement of the electrochemical performance of the composite. Moreover, the specific capacitance of PMGF is much larger than that of MnO2/GF (MGF), which may be ascribed to the participant of PANI, which contributes additional pseudocapacitance and electron transport path. POLYM. COMPOS., 34:819-824, 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A novel conjugated polymer containing electron transport groups with high electron affinity, denoted POXD was synthesized upon polycondensation. The polymer was characterized by Fourier transform infrared (FTIR) spectra and 1H nuclear magnetic resonance (1H NMR) spectroscopy. Furthermore, the conjugated polymer/graphene (POXD/RGO) composite film was prepared, which was subsequently used as the support for the electrodeposition of platinum. The microstructure and morphology of the prepared samples were characterized by X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM). The electrocatalytic activity for the oxidation of methanol was investigated through cyclic voltammogram method. The POXD/RGO composite film can facilitate the electrodeposition of Pt nanoparticles compared with graphene (RGO) support. The POXD/RGO/Pt composite exhibits more excellent electrocatalytic property for the oxidation of methanol, such as lower oxidation potential and higher current intensity, which might be attributed to the high electron affinity of the polymer and the interaction of the Pt nanoparticles with polymer. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Conducting poly(3-acetylpyrrole) (PAPy)/multiwalled carbon nanotubes (MWNTs) composites were synthesized by the in situ chemical polymerization of 3-acetylpyrrole (APy) onto MWNTs. The structure and morphology of the PAPy/MWNT composites were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis. The FTIR results indicated that no chemical reaction occurred between the PAPy and MWNTs, and only the MWNTs served as a template for APy polymerization. FE-SEM and TEM suggested that PAPy was only coated on the surface of the carbon nanotubes, and the thickness of the PAPy coating on each nanotube was dependent on the ratio of APy to MWNTs. The standard four-probe method was used to measure the electrical conductivity of the samples at room temperature, and the results show that the MWNTs enhanced the electrical conductivity of the composites compared to PAPy. In addition, the solution stability of the suspension with the PAPy [or polypyrrole (PPy)]/MWNT composites was investigated; this showed that the dispersion of the PAPy/MWNT composites in ethanol solution was much better than that of the PPy/MWNT composites. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Cover Feature: In-situ Copper Doping with ZnO/ZnS Heterostructures to Promote Interfacial Photocatalysis of Microsized Particles (2/2021) Keywords: Photocatalysis; ZnS/ZnO; Heterostructure; In-situ copper doping; Solar energy EN Photocatalysis ZnS/ZnO Heterostructure In-situ copper doping Solar energy 489 489 1 01/28/21 20210120 NES 210120 B The Cover Feature b shows a little cat looking at a microsized particle which is like an egg tart. Photocatalysis, ZnS/ZnO, Heterostructure, In-situ copper doping, Solar energy. [Extracted from the article]