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Superior performance fillers are considered as an effective means to enhance the performance of carbon/graphite composites. However, poor interfacial properties and incomplete filler networks limit the performance enhancement of the composites. In this study, a new method was proposed to weaken this impact through the synergistic effect of the electrostatic self-assembly of nano carbon black (NCB) onto carbon nanotubes (CNTs). The results showed that the synergistic effect between NCB and the CNTs significantly improved the mechanical and electrical properties of the composites. NCB reduces the porosity of the composites and increases the interaction between the CNTs and matrix. The compressive strength of the composite was 143.2 Mpa, and the flexural strength was 46.3 MPa, which is 210% higher than that of the pristine carbon/graphite composites. Moreover, NCB and CNTs form a globally connected synergistic network in the carbon skeleton. Composites filled with CNTs/NCB exhibited the lowest resistivity and highest thermal conductivity, with a resistance that was 42% lower than that of pristine carbon/graphite composites at 44.8 μΩ m. All of these results suggest that the synergistic effect of CNTs/NCB show great potential to improve the performance of carbon/graphite composites. [Display omitted] • NCB was self-assembled with CNTs by electrostatic force, forming an enhanced phase with synergistic effect. • Targeted improvement of matrix properties near CNTs using NCB can enhance the interfacial properties. • Self-assembly of CNTs with NCB forms a synergistic network in the composite to enhance electrical and thermal properties. [ABSTRACT FROM AUTHOR]

This paper investigated the influence of carbon black (CB) and carbon nanotube (CNT), used at 0–1%, by volume, on mechanical performance and piezoelectricity of 0–3 γ–C 2 S–based piezoelectric composite. The γ–C 2 S–based piezoelectric composite was prepared through carbonation of the proportioned mixture. Parameters d 33 , g 33 , and ε r were characterized with the CB and CNT additions. The influence of PZT size and volume on these parameters were also studied. Tested results showed that a greater PZT average size and volume significantly improved the d 33 , g 33 , and ε r values of γ–C 2 S–based piezoelectric composite given the increased contact among PZT particles. The use of 1.0% CB can lead to 50% and 265% enhancements in d 33 and ε r , respectively. Such improvements in d 33 and ε r values were 50% and 190%, respectively, with the addition of 0.3% CNT. This is attributed to the enhanced conductivity of γ–C 2 S–based piezoelectric composite, which can promote the poling of PZT particles. Moreover, the compressive strength of γ–C 2 S–based piezoelectric composite were improved by 12 and 3 MPa with the use of CB and CNT, respectively. In addition, the γ–C 2 S–based piezoelectric composite had 2–6 folds greater d 33 and ε r values given the similar CB and CNT contents relative to those of cementitious piezoelectric composite. Therefore, the use of CB and CNT can advance the development of γ–C 2 S–based piezoelectric composite with enhanced mechanical performance and piezoelectricity. [ABSTRACT FROM AUTHOR]

TiC/Al–Cu nanocomposites were fabricated in Al–Ti–C powder systems using carbon black, a mixture of C and carbon nanotubes (C + CNTs), and CNTs via an in-situ method involving combustion synthesis and hot pressing. As the carbon source changed from pure carbon black to the C + CNT mixture and pure CNTs, the size of the TiC nanoparticles decreased gradually. The nanocomposites synthesized based on the C + CNT mixture exhibited the most uniform dispersion of TiC nanoparticles. The 30 vol% TiC/Al–Cu nanocomposite prepared from the C + CNT mixture had the best comprehensive mechanical properties (yield strength (411 MPa), compressive strength (712 MPa), fracture strain (17.2%), hardness (206.8 HV), and wear resistance under the experimental conditions due to having the most uniformly dispersed TiC nanoparticles. The wear mechanism was a combination of plastic deformation, abrasion, and adhesion. This method may be a low-cost and convenient means to control the sizes of in-situ TiC nanoparticles and prepare high-performance TiC/Al–Cu nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, different carbon sources, such as nano-sized carbon black (CB), carbon nanotubes (CNT), carbon fibers (CF) and graphene (GR), were reacted with titanium micro-powders, to synthesise titanium carbide (TiC) in the mixed molten salts of LiCl–KCl–KF at 1100 °C for 6 h. There experiments were performed to investigate the accuracy of "carbon-template-growth" mechanism for the formation of TiC, that was proposed previously using micro-sized titanium and submicro-sized CB powders. The products synthesised from the different carbon sources were observed and characterised by scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results showed that the visual morphologies of the TiC products mainly retained the shapes of the as-received carbon sources, that is, they presented an equiaxed-shape with a grain size of 10–20 nm from CB, a shell layer along the outer surface of the CNTs and CF, and a flake-shape with the GR. These morphologies reveal that the formation of TiC is indeed controlled by the "carbon-template-growth" mechanism. [ABSTRACT FROM AUTHOR]

Abstract Recently, in order to increase the electrical conductivity of the phosphorus-based anode materials and to alleviate the deterioration of the electrochemical performance caused by the volume expansion of red phosphorus, the composite material made of red phosphorus and carbon matrix has become the mainstream route for lithium ion batteries. In this work, we used one-pot ball milling method to synthesize an unique rebar-reinforced concrete structure hybrid of nanosized phosphorus particles, multi-walled carbon nanotubes, and carbon black (CNTs/CB@P composites). The carbon nanotubes formed a primary frame network structure and the CB formed a regional secondary network structure in the CNTs/CB@P composites, which makes red phosphorus covered by double network structure. Such a structure greatly improves the conductive network of CNTs/CB@P composites for lithium ion batteries. Furthermore, this one-pot ball milling method was simple, continuous, and much suitable for industrial production. When the ratio of multi-walled carbon nanotubes to carbon black was 3:2, the CNTs/CB@P composites had the cycling performance with a reversible capacity of ~ 474.9 mAh g−1 and a capacity retention of ~ 56.3% after 50 cycles. [ABSTRACT FROM AUTHOR]

Abstract: Development of low carbon containing MgO-C refractories has been studied containing a fixed 0.9wt% of nano carbon and 1–9wt% of flake graphite. Refractory compositions were prepared and processed as per the conventional manufacturing techniques of MgO-C refractory. Properties of the different compositions were evaluated and also compared against the conventional MgO-C refractory containing 10wt% graphite prepared under exactly similar conditions. Addition of 3wt% of flake graphite in combination with 0.9wt% of nano carbon black was found to be optimum and resulted in better/comparable properties to that of conventional MgO-C refractory. [Copyright &y& Elsevier]