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In response to the increasing concern for energy management, molybdenum disulfide (MoS 2 ) has been extensively researched as an attractive anode material for sodium-ion batteries (SIBs). The proficient cycling durability and good rate performance of SIBs are the two key parameters that determine their potential for practical use. In this study, nature-inspired three-dimensional (3D) MoS 2 ultrathin marigold flower-like microstructures were prepared by a controlled hydrothermal method. These microscale flowers are constructed by arbitrarily arranged but closely interconnected twodimensional ultrathin MoS 2 nanosheets. The as-prepared MoS 2 microflowers (MFs) have then been chemically wrapped by layered graphene sheets to form the bonded 3D hybrid MoS 2 -G networks. TEM, SEM, XRD, XPS, and Raman characterizations were used to study the morphology, crystallization, chemical compositions, and wrapping contact between MoS 2 and graphene. The ultrathin nature of MoS 2 in 3D MFs and graphene wrapping provide strong electrical conductive channels and conductive networks in an electrode. Benefitting from the 2 nm ultrathin crystalline MoS 2 sheets, chemically bonded graphene, defect-induced sodium storage active sites, and 3D interstitial spaces, the prepared electrode exhibited an outstanding specific capacity (606 mA h g −1 at 200 mA g −1 ), remarkable rate performance (345 mA h g −1 at 1600 mA g −1 ), and long cycle life (over 100 cycles with tremendous Coulombic efficiencies beyond 100%). The proposed synthesis strategy and 3D design developed in the present study reveal a unique way to fabricate promising anode materials for SIBs.

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A new test technique has been developed in order to characterise the skincore interfacial properties of a series of fibre reinforced sandwich structures similar to those presently being used in the marine industry. The technique involves peeling the lower surface skin away from the core in a controlled fashion. Four different glass fibre reinforced epoxy/balsa structures have been tested and the effect of incorporating various skin-core interlayers assessed. Tests were also undertaken on specimens that had been immersed in seawater for a period of forty-five days. The results indicate that the fracture energies associated with skin-core debonding are relatively high, typically 1000 J/m2. It has also been shown that neither a pre-treatment of the balsa core nor the incorporation of a layer of CSM fibres resulted in an improvement in the fracture energy of the interfacial region. Immersion in seawater for forty-five days resulted in a significant increase in the fracture toughness of this region. A subsequent examination of the fracture surfaces showed that fibre bridging between the GFRP skin and the balsa core was more extensive in the soaked samples.

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This work presents a correlation between the transverse permeability of a preform and the process variability of the automated dry fiber placement manufacturing technique. In this study, an experimental and numerical analysis of the dry tape preform, with a focus on its through-thickness permeability, has been undertaken. Geometric models, containing flow channels of two different width dry tape carbon preforms, have been created in the TexGen modeller. A Computational fluid dynamics (CFD) simulation has been undertaken to obtain the predicted through-thickness-permeability of the dry tape preform. A parametric study on the effect of different dry tape gap sizes on the permeability of the preform is presented. An in-situ compaction study, carried out in an X-CT machine, revealed that the gap sizes were irregular throughout the manufactured preforms. In addition, an experimental investigation of the through-thickness permeability, which is based on a saturated flow condition at a thickness corresponding to full vacuum pressure, is also presented. The permeability prediction based on the X-CT re-constructed geometric model has been validated using the experimental data. A further parametric study has revealed that the process variablity in automated dry fibre placement influences the through-thickness permeability by a factor of upto 5.