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Nanotechnology offers fundamentally new capabilities to architect a broad array of novel materials, composites and structures on a molecular scale. It is potentially capable of redefining the methods used for developing lighter, stronger, high-performance structures and processes with unique and nontraditional properties. This review summarizes different classes of nanocarbon-based polymer composites and their applications. Also, it highlights different ways to create smaller, cheaper, lighter and faster devices using nanocarbon-based polymer composites. The potential applications of such materials are in the fields of membrane, aviation, electronics, polymer composites, as well as the marine and transport industries. A detailed description of nanocarbon-based composite materials manufactured from PE, PP, PS, PS, PVC, PPS, ABS, PMMA, nitrile rubber, etc. is also reviewed. Some of the major applications of carbon-based polymer nanocomposites are in the tyre industry, semiconductors, and many more, which has brought about the new, developing and exciting research field called nanoscience.

The mixed LiMn₂O₄ and carbon black were served as anodes for lithium-ion batteries and the samples with high active material utilization ratio showed the highest capacity and cycling retention of 407.0 mAh/g after 50 charge/discharge cycles. The galvanostatic cycling and electrochemical impedance measurements were used to study their electrochemical performances. The commercial carbon black showed higher cycling retention, 162.0 mAh/g after 50 charge/discharge cycles. The present results confirmed that the capacity and cycling retention of LiMn₂O₄ anodes can be improved by the increase of conductivity in lithium-ion batteries, which can increase the utilization ratio of active materials.

In this study, carbon black (CB) powder-loaded polyurethane (PU) composites (CB–PU composites) were prepared by melt mixing method with different volume percentages (45, 50, 55, 58 and 61 vol.%) of CB in the PU matrix. The prepared CB–PU composites had been further studied for surface morphology using the field-emission scanning electron microscopy (FESEM) technique. Dielectric properties in terms of real permittivity ($𝜀\prime )$ and imaginary permittivity ($𝜀\prime \prime )$ of the fabricated composites were computed using an Agilent E8364B vector network analyzer in the frequency range of 8–12 GHz ($X$-band). Dielectric loss factor of the prepared CB–PU composites was computed in terms of the dielectric loss tangent (tan ${\delta }_e$ = $𝜀\prime \prime$/$𝜀\prime )$. Microwave absorbing properties were appraised in terms of the reflection loss (RL) which in turn was calculated for varying thicknesses of the prepared composites from the measured real and imaginary permittivity data. The minimum RL was observed as −20.10 dB for the absorber with a thickness of 2.2 mm and the bandwidth achieved was 1.92 GHz for RL $\le -$10 dB. Based on the above results these CB–PU composites have potential use as effective microwave absorbers in 8–12-GHz ($X$-band) frequency range.

Two kinds of carbon black (CB) (i.e., CB#300 and CB#3350) were added into poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP), respectively, to improve its piezoelectricity. The results revealed that when 0.5 wt.% CB was added, the best performance of the PVDF-HFP/CB composite films was obtained. The calibrated open circuit voltage and the density of harvested power of 0.5 wt.% CB#3350 contained composite films were 204%, and 464% (AC) and 561% (DC) of those of neat PVDF-HFP films. Similarly, for 0.5 wt.% CB#300 contained films, they were 211%, and 475% (AC) and 624% (DC), respectively. The enhancement mechanisms of piezoelectricity were clarified by the observation of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and scanning electron microscope (SEM). We found that the added CBs act as nucleate agents to promote the formation of elongated, oriented and fibrillar β-phase crystals during the fabrication process, which increase the piezoelectricity. Overdosed CBs lead to a lower crystallinity degree, resulting in the lower piezoelectricity. Compared with CB#3350, CB#300 performs slightly better, which may be ascribed to its higher specific surface area.