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A novel carbonized phenolic formaldehyde resin (PF) resin-coated Ni foam was used as an interlayer for brazing carbon fiber reinforced carbon composites (C/C) and Nb using a Ti–Ni filler. At first, uniformly distributed carbonaceous laminae with different mass fractions on the Ni foam surface were acquired after the carbonization process by controlling the concentration of the PF solution. Afterwards, the obtained carbonaceous laminae covered Ni foam composite (C-Nif) was applied as an interlayer for brazing C/C and Nb via an assembly of C/C/Ti foil/Ni foil/C-Nif interlayer/Ti foil/Nb. The morphologies and microstructures of the carbonization product and the interfacial microstructures of the joints were investigated. The brazing mechanism has been elaborated in detail. With the help of the interconnected porous structure of the Ni foam, the distribution of the in-situ formed (Ti,Nb)2Ni particles, (Ti,Nb)C ring reinforcements as well as the Nb solid solution were uniformly obtained throughout the brazing seam. As a result, the joint residual stress was effectively released and consequently, the joint shear strength at elevated temperature (1000 °C) reached up to 33 MPa, which is 4.5 times higher than the directly brazed joint without an interlayer.

In this work, three masterbatches of carbon nanotubes (CNTs) were utilized to manufacture electrically and thermally conductive epoxy nanocomposites at three weight percentages using a scalable, economic processing route. Two masterbatches contained multi-wall carbon nanotubes (MWCNT) of similar aspect ratios while the third contained single-wall carbon nanotubes (SWCNTs) with a higher aspect ratio. Each masterbatch was produced industrially using a different processing technique. It was seen that the functional properties of the produced nanocomposites were directly tied to the particle dispersion and the masterbatch production route. For samples produced with better masterbatch production technology (SWCNTs), the dispersion degree was better compared to samples produced using less effective production techniques (MWCNTs). Electrical and thermal conductivity for SWCNT nanocomposites reached as high as 0.5 S/cm and 0.48 Wm−1 K−1 at 2.0% wt. respectively, whereas MWCNT samples showed values between 1.37×10−5 – 1.5×10−7 S/cm and 0.22 Wm−1 K−1 for electrical and thermal conductivity at the same weight percentage. SWCNT samples outperformed MWCNT samples by 4–6 orders of magnitude in terms of electrical conductivity and 4 times for thermal conductivity.

Antimony (Sb), a typical anode material in sodium-ion batteries (SIBs), undergoes sharp capacity fading due to large volume changes during electrochemical cycling. To solve this issue, recent research has focused on designing Sb with special morphologies or introducing another component as a buffer to generate Sb-based composites. In this study, the above two strategies were combined, focusing on a nanoporous Sb/polyaniline (NP-Sb/PANI) anode where PANI was directly coated on the surface of NP-Sb by in situ oxidative polymerization. This composite anode demonstrated enhanced performance, delivering an initial reversible capacity of 510 mAh g−1 and showed capacity retention of up to 82.4% after 250 cycles at a C-rate of C/2. The improved electrochemical performance is attributed to the synergetic effect of NP-Sb and conductive PANI. Specifically, the porosity in NP-Sb can accommodate the volume variation and facilitate electrolyte penetration into the electrodes, while the PANI coating can further buffer the volume expansion and improve the diffusion rate of sodium ions in the electrode.

Masterbatches of single wall carbon nanotubes (SWCNTs), multi-wall carbon nanotubes (MWCNTs), graphene (G), reduced graphene oxide (RGO) and nitrogen doped graphene (NDG) were used at 0.5, 1.0, and 2.0 wt% to produce electrically conductive and piezoresistive nanocomposites. The conductivity and piezoresistive response was dependent on the microstructure obtained. A unified processing route incorporating mechanical mixing and ultrasonication was used. Distance between electrode points affected the final measurements and a minimum measurement distance of 2 cm was identified. Digital image correlation (DIC) was employed to measure strain during tensile loading. For all materials, an increase in the wt.% of nanoparticles resulted in lower resistivity. Resistivities for CNT samples ranged between 2 and 106 Ohm⋅cm as compared to G/RGO/NDG samples, 1011–1012 Ohm⋅cm. Strain based gauge factors for CNT samples ranged up to ~ 7 while to G/RGO/NDG masterbatches were found to be unsuitable for self-diagnostic applications.