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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]

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]

The rapid progress in miniaturization and integration of semiconductor power devices has made heat dissipation a critical concern in the development of high‐performance semiconductor devices, thereby increasing the demands for the heat transfer efficiency of polymer composites. To address this issue, an efficient three‐dimensional (3D) heat conduction network structure is constructed in the polymer matrix by leveraging the mutual reaction of amino and epoxy groups on the surface of the filler treated by coupling during the melt mixing process, this approach leads to an enhancement in the thermal conductivity of the composites. First, the inert surfaces of graphene nanosheets (EX‐G) and carbon fibers (CF) are coated with polydopamine (PDA) to form active sites. Subsequently, the graphene (EX‐G), alumina (Al2O3), and carbon fiber (CF) are treated with an amine coupling agent (KH550) and epoxy coupling agent (KH560), respectively. Notably, at a filler content of 25 wt%, the thermal conductivity (TC) of the composites increases by approximately 282% compared to pure nylon 6. This research contributes novel insights into the field of thermally conductive polymer composites. Highlights: The surface of the EX‐G and CF covered by PDA generates active sites.Fillers reduce the interface thermal resistance through chemical bonds.Fillers surface reaction builds a 3D thermal conductive network.3D network structure can significantly improve the TC of composites.Only 25 wt% of hybrid fillers in a 282% increased TC of composites. [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]

Ethylene‐vinyl acetate copolymer (EVA) has been widely used for packaging materials for decades. However, EVA was highly restricted due to the poor thermal stability and anti‐static performance. For enhancing thermal stability and anti‐static performances, a large number of additives were added to EVA, which seriously prejudice the processability and mechanical properties of the polymer. To address this problem, N‐doped reduced graphene oxide@Fe2O3 (RGF) was constructed as a heat and electronic conduction actor in EVA matrix in this work. As as‐prepared RGF composites shown, Fe2O3 particles well dispersed on the surface of RGO sheets, forming a point‐plane three‐dimensional structure. Therefore, the thermal conductivity and volume resistivity of the EVA composites reached 0.58 W/mK and 1.7 × 1010 ohm∙cm at 1.0 wt.% of RGF addition, which shows 284% folds increasement and 7 orders of magnitude decrement than neat EVA. Moreover, the storage modulus and thermal stability of EVA composites at 180°C were also improved. In sum, all those enhancements were attributed to the Fe2O3 particles well dispersed on RGO sheets, and amino groups from RGF provided mass of hydrogen bonds with EVA chains which provide more sites and path for heat and electronic conduction. In this work, RGF composites and its synthesis strategy show potential promising in the highly effective thermal and electrical exchange materials. [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]