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Lithium–sulfur (Li–S) batteries are the most promising next-generation energy storage devices owing to their excellent theoretical specific capacity (1675 mA h g−1) and the abundant availability of sulfur resources at low costs. However, serious shuttle effects and sluggish reaction kinetics obstruct the practical implementation of Li–S batteries. Herein, a functional separator modified with polytetraphenylporphyrin cobalt adsorbed onto multi-walled carbon nanotubes (PTPPCo/MWCNT) was fabricated by a simple vacuum filtration method. Because of the excellent conductivity of the MWCNT as well as the enhanced chemical adsorption and powerful catalytic activity of PTPPCo, the shuttle effect was effectively suppressed and the reaction kinetics were greatly enhanced. Consequently, the Li–S cells with the modified functional separator PTPPCo/MWCNT showed a prominent initial reversible capacity of 1330 mA h g−1 at a current density of 0.2C, enhanced rate performance, outstanding cycling stability (with a slight average capacity decay of 0.038% per cycle at 2C for 500 cycles), and excellent anti-self-discharge ability.

The unique features of bioresources such as cellulose and bio-wax include renewability, biodegradability, low cost, and abundance on Earth. Therefore, their efficient use is essential for a sustainable economy. Herein, we report a facile method for the surface modification of pretreated cotton with a bio-wax emulsion in water and Fe3O4 nanoparticles to fabricate a green, durable, magnetic, and superhydrophobic/superoleophilic absorbent for the sorption of oil and organic solvents. Magnetic superhydrophobic cotton (MSC) was successfully prepared via a simple two-step dip-coating method without using any toxic organic reagents. The as-prepared MSC was used to selectively absorb various types of oils and organic solvents up to approximately 20-50 times its own weight. Furthermore, it exhibited a stable magnetic responsivity and high reusability in oil/water separation cycles. In addition, the removal and collection of the absorbed oil/organic solvents were easily achieved with distillation and a vacuum air pump. Moreover, the as-prepared MSC was used in a heavy oil/water gravity-separation filter system and in the continuous collection of a light oil from water surfaces using a pump. The proposed concept may provide a green and sustainable strategy for fabricating superhydrophobic/superoleophilic materials for efficient sorption of oils and organic solvents.

Herein, we report a synthesis of multicomponent Pt/PtTe2/NiCoTe2 and N, P, F ternary doped carbon composites showing a morphology of folded hollow microspheres (Pt/PtTe2/NiCoTe2/NPFC HFSs) by a facile hydrothermal method with the assistance of ionic liquid. Pt, PtTe2, and NiCoTe2 produced by one step of tellurization process were encapsulated in carbon, which protected Pt/PtTe2/NiCoTe2 from corrosion in acidic and alkaline conditions. The synergistic effects of Pt/PtTe2/NiCoTe2 can improve the HER performance. With the addition of ionic liquid, abundant folds and N, P, F ternary doped carbon were obtained, leading to increased specific surface area, faster electron transfer, as well as more active sites. Thanks to these advantages, Pt/PtTe2/NiCoTe2/NPFC HFSs show excellent performance in HER (when the current density achieved 10 mA cm−2, the overpotentials were respectively 34, 43, and 36 mV in acidic (0.5 M H2SO4), alkaline (1 M KOH), and neutral (1.0 M PBS) solutions. This study offers a simple strategy for modifying the morphology and element doping to enhance electrochemical performance.

A fairy simple and environmental hydrothermal method is successfully found to synthesize the anode materials integrated by NiFe2O4 (NFO) and ultrathin flake graphite (UFG)，which are denoted as NFO/UFG composites. Then a couple of experiments have been implemented in order to search for the most profitable proportion of UFG in the composite. And it's finally attested that NFO/UFG-2 composite exhibits the most beneficial morphology structure which is characterized as three-dimensional floral NFO microspheres assembled by many porous nanosheets anchored on the pedestal of UFG by SEM test and further TEM measurement. Not only that, the NFO/UFG-2 composite is also investigated to acquire the best electrochemical performances. It shows a most stable long-term cycling performance with a high initial coulombic efficiency of 83.4% and even obtains a high specific capacity of 963.4 mAh g-1 after 300 cycles at a current density of 200 mA g-1 and remarkable reversibility not only at low current densities but also at high current densities. Satisfactorily the good synergy of porous NFO and UFG significantly enhances the electronic conductivity and relieves the huge bulk expansion of traditional transition metal oxide. This unique electrode material is demonstrated to be a promising candidate for the new-generation LIBs.

A new route for the in-situ formation of silver-polypyrrole (Ag-PPy) on the layer of SiO2@poly(sodium styrene sulphonate) (SiO2@PSS/Ag-PPy) composite particles, using SiO2@poly(sodium styrene sulphonate) (SiO2@PSS) particles as a template is presented. The template SiO2@PSS consisting of a SiO2 core and PSS on the surface was prepared by the ‘grafting from’ approach. SiO2@PSS/Ag-PPy was characterised by transmission electron microscopy, X-ray powder diffraction, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopic analysis, thermo-gravimetric analysis and differential thermal analysis. The results showed that the SiO2@PSS/Ag-PPy composites consisting of a spherical structure with a diameter of about 80 nm were successfully fabricated.

A polypyrrole (PPy) using TiO2 nanotube@poly(sodium styrene sulfonate) (TiO2@PSS) as dopant and template was synthesized by chemical oxidation polymerization. The template TiO2@PSS consisting of a TiO2 nanotube core and PSS on the surface was prepared by a “grafting from” approach. PPy on the layer of TiO2@PSS (TiO2@PSS/PPy) was characterized by transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectrometry (FTIR), Raman spectroscopic analysis, UV-visible (UV-vis) spectroscopy, thermo gravimetric analysis, and electrical conductivity analysis. Results showed that TiO2@PSS/PPy was successfully fabricated. The electrical conductivity of the TiO2@PSS/PPy nanocomposites at room temperature was 11.6 S cm−1, which was higher than that of the PPy (4.2 S cm−1). This result was consistent with those based on FTIR, UV-vis spectroscopy, and XPS analyses. The nanocomposites have nanoparticle size and controllable morphology and thus potential applications in photoelectrochemical devices, photocatalytic devices, conductive inks, electronic printing sensors, and electrodes. POLYM. COMPOS., 2014. © 2014 Society of Plastics Engineers