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The dissipation of static charge generated by contact electrification occurs readily into all interfaces of matter via different fundamental mechanisms and critically affects the desired level of steady-state charge in practical applications.

An oxygen-vacancy-rich Fe3O4/carbon nanosheets composite is fabricated from Fe3+-gluconate complex as precursor using a spontaneous foaming strategy. The composite has a unique 2D structure and exhibits superior microwave absorption capability.

To expand the applications of graphene which has so far been limited by the expensive nature of single-layer graphene, the effects of varying percentages of low-cost functionalized multilayer graphene nanosheets in siloxane-modified organic coatings were studied. The hydrophobic organic siloxane–acrylic resin was prepared by solution polymerization of acrylic monomers, and the graphene nanosheets were functionalized using fluorosilane. The coatings were sprayed on the LY12 aluminum substrate, and the wettability, anticorrosion, conductive, and accelerated weathering behaviors were comprehensively examined. It is shown that the increasing addition of functionalized graphene nanosheets increases the water contact angle and the surface conductivity. At 5% graphene loading, coating–substrate adhesion remains almost unchanged, while the electrochemical impedance parameters revealed good anticorrosion performance up to 10% loading. The surface measurements and Fourier transform infrared spectroscopy (FTIR) results confirmed the photostabilization ability of graphene loading in acrylic coatings during the accelerated weathering test. Also, the mechanical properties of the coatings were not damaged during the exposure, and pitting corrosion sites were observed only on the 20% graphene-filled coatings after 1000 h of exposure. These integrated analyses of mechanical properties and environmental accelerated tests are beneficial to engineering applications of graphene coatings.

Solid polymer electrolytes (SPEs) with good flexibility and low cost are very promising for all-solid-state lithium metal batteries, but they suffer from the trade-off between ionic conductivity at room temperature and mechanical stability. Herein, a robust composite polymer electrolyte is prepared by thermal lamination of PEO polymer electrolyte films onto a lithiated organic nanofiber membrane (LOF), which could combine the merits of 3D Li-ion conduction highways for high ionic conductivity and nanofiber-reinforced networks for good mechanical properties. The intimate combination between the nanofibers and the PEO matrix endows the LOF-reinforced PEO composite (LOF-CPE) with homogeneous structure, leading to an enhanced ultimate tensile stress of 8.9 MPa. Furthermore, the introduction of the LOF significantly decreases the crystallinity of the polymer matrix, which accelerates polymer segmental motion. The well-designed LOF also constructs an interfacial percolation network with additional active Li+, resulting in the formation of high-speed Li-ion conduction pathways. Therefore, the as-prepared LOF-CPE delivers an excellent ionic conductivity of 7.41 × 10−5 S cm−1 at 30 °C. While used as a SPE in LiFePO4|Li solid-state batteries, the batteries exhibit good cyclability with a capacity retention of 82% after 500 cycles under 0.5C. This work provides a very promising strategy for solid polymer electrolytes to simultaneously achieve high ionic conductivity and excellent mechanical properties towards high-performance solid-state lithium metal batteries.

Threatened by the energy crisis and environmental pollution, most countries in the world are vigorously developing new energy vehicles to promote low-carbon environmental protection and boost a green transportation system. Based on the intelligent manufacturing standard system, this study constructed a new energy vehicle intelligent manufacturing development-influencing factor model. Taking the intelligent manufacturing development ability as the dependent variable, taking external environment factors, commonalities among the new energy vehicle enterprises, and industry progress as independent variables, five hypotheses are proposed. This study used a structural equation model to test the hypotheses and reveal the mechanism of how factors influence the new energy vehicle intelligent manufacturing. The results show that external environment factors and industry progress directly and positively affect the development capability of intelligent manufacturing of new energy vehicles, while the commonalities among the NEV enterprises have an indirect effect through industry progress on intelligent manufacturing of new energy vehicles. Based on the analysis, this study puts forward some suggestions for better development of new energy vehicle intelligent manufacturing.

Graphene-based membranes have great potential to revolutionize nanofiltration technology, but achieving high solute rejections at high water flux remains extremely challenging. Herein, a family of ultrafine metal oxide/reduced graphene oxide (rGO) nanocomposites are synthesized through a heterogenous nucleation and diffusion-controlled growth process for dye nanofiltration. The synthesis is based on the utilization of oxygen functional groups on GO surface as preferential active sites for heterogeneous nucleation, leading to the formation of sub-3 nm size, monodispersing as well as high-density loading of metal oxide nanoparticles. The anchored ultrafine nanoparticles could inhibit the wrinkling of the rGO nanosheet, forming highly stable colloidal solutions for the solution processing fabrication of nanofiltration membranes. By functioning as pillars, the nanoparticles remarkably increase both vertical interlayer spacing and lateral tortuous paths of the rGO membranes, offering a water permeability of 225 L m−2 h−1 bar−1 and selectivity up to 98% in the size-exclusion separation of methyl blue., Graphene oxide nanofiltration membranes with tunable interlayer spacing tend to be either unstable in water or have low water permeation rates. Here the authors report a general synthetic method to achieve ultrafine metal oxide - reduced graphene oxide nanocomposites for dye filtration, achieving high water permeability and selectivity.

Glycerol was converted to pyridine bases through a continuous two-step process in a series-connected two-stage fixed-fed reactor. Firstly, dehydration of glycerol to acrolein was achieved in high selectivity over a catalyst FeP-P in the first reactor. The dehydration products were directly introduced into the second reactor charged with a bimetallic catalyst Cu4.6Pr0.3/HZSM-5, contacting ammonia over the catalyst to afford pyridine bases in high yield. Under optimized reaction conditions, the conversion of glycerol was 100%, and the total yield of pyridine base reached up to 60.2%. The catalyst characterization results revealed that the doping of copper and praseodymium did not destroy the frame work of HZSM-5, but increased the Lewis acidity of the catalyst which enhanced the activity and selectivity of the catalyst in the conversion of acrolein to pyridine bases. The doping of minute amount of praseodymium led to the high dispersion of the CuO nanoparticles, thus enhanced the dehydrogenation activity of CuO species, and finally improved the performance of the bimetallic catalyst. In addition, the interaction of copper and praseodymium in the bimetallic catalyst might have positive effect on the performance of the catalyst in the conversion of acrolein to pyridine bases.

Compression of a film/substrate bilayer system with different surface/interfacial structures can lead to diverse buckling patterns including sinusoidal wrinkles, ridges, folds, creases and tilted sawteeth wrinkles. In this paper, we show that elastic wave band gaps in the film/substrate bilayer system largely depend on the wrinkling patterns. More interestingly, we find that different wrinkling patterns investigated here can coexist and evolve in one bilayer system and the elastic wave propagation behaviors can be controlled by manipulating the hybrid wrinkling patterns. Our analysis also reveals that the periodic stress pattern plays a dominant role in tuning the bandgap structures in comparison to geometrical patterns caused by surface instability. A careful investigation of the transmission spectra of the composite systems has validated the main findings given by the analysis based on the Bloch wave theory. Potential use of the method and materials reported here to gain wide attenuation frequency ranges and the design of nesting Fibonacci superlattices have been demonstrated.

Sinusoidal wrinkling will occur in a planar film-substrate bilayer when the uniaxial compressive strain imposed to the system exceeds a critical value. However, when a core-shell soft cylinder is subjected to axial compression, surface wrinkling patterns may evolve from the sinusoidal mode to the diamond-like mode, depending on the modular ratio and the curvature of the system. Inspired by this phenomenon, we here propose a simple yet robust strategy to fabricate hierarchical wrinkling patterns by controlling the curvature of a film-substrate system. To quantitatively understand the experimental results, a three-dimensional finite element model has been built to track the wrinkling pattern evolution. Furthermore, a phase diagram is provided based on the theoretical analysis and finite element simulations, which may guide the experimental design. In addition, the wetting properties of the surface with hierarchical micropatterns fabricated using the proposed method are investigated. The results show that the hierarchical surface wrinkles lead to anisotropic wetting behavior, which can be tuned by controlling the imposed compressive strain. The tunable anisotropic wetting surface fabricated here may find a broad range of applications such as in the development of sensors, fluidic devices, micro-reactors and biomedical devices.