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A fast and convenient method to create n-doped or p-doped carbon nanotube (CNT) films of improved electrical conductivity is presented herein. Free-standing thin flexible films made from unsorted CNTs and composed of predominantly (6,5) or (7,6) chiral angle were exposed to hydrazine (N2H4) or boron trifluoride (BF3) solutions, which decreased the sheet resistance by almost up to an order of magnitude. Analysis of the CNT films surface chemistry indicates that despite benign influence of the dopants on their composition, they strongly, but favorably affected electronic structure. Depending on the type of employed dopant, the Fermi level was strongly shifted upwards or downwards to enhance conduction of electrons or holes for employed n-doping and p-doping agents, respectively. This work provides an effective approach for the formation of CNT or graphene-based macroscopic assemblies such as films or fibers of high electrical conductivity with predetermined type of predominant charge carriers without excessive processing. ; The Silesian University of Technology (Grant Agreement - 04/020/RGH17/0050). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

The discovery of carbon nanotubes (CNTs) revealed that this new form of carbon can challenge traditional materials on many fronts. Remarkable electrical, thermal, mechanical and optical properties of individual CNTs have attracted significant attention, and so scientists have begun to consider their implementation in the everyday life. Unfortunately, CNT aggregates are composed of a wide range of CNT types, which has a strongly negative influence on the observed performance of macroscale devices made from them. Recently, however, it has become evident that different CNT types can be sorted according to length, diameter, electrical character, chiral angle and even handedness, which reignited interest in them. This review aims to demonstrate the state-of-the-art of all the mainstream methods of sorting CNTs (preferential synthesis, selective destruction, (di)electrophoresis, ultracentrifugation, chromatography, (co)polymer isolation and aqueous two-phase extraction). It is concluded with an overview of already tested applications using sorted CNTs and gives overlook of the field for the future. ; The Silesian University of Technology (Grant Agreement - 04/020/RGH17/0050). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

Recently, copper-nanocarbon composites have become the focal point of many research groups around the world. The reason for this phenomenon is that carbon nanotubes or graphene have proven that they can bring the technology of copper to a whole new level due to their extraordinary electrical, thermal and mechanical properties. Addition of even small amounts of nanocarbon into copper matrix can significantly enhance its performance, but unfortunately integration of these two materials is not trivial. In this review article we highlight methods of manufacture of Cu-nanocarbon composites and properties of the resulting material. We stress their strong and weak points as well as indicate pending challenges remaining to be sorted out to produce the nanocomposite of significantly improved properties as compared to neat Cu. Finally, we identify future R&D directions, which must be taken to bring these materials closer to mass-production and eventually real-life applications. ; National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

Development of a method of formation of chiral free-standing films from carbon nanotubes (CNTs), which circumvents the limitations of the established techniques, is presented. CNT macroassemblies of any size and shape can be made from desired CNT feed including those synthesized or sorted with the objective of chirality control. Free-standing CNT films were created from various starting CNT materials the most interesting being of predominantly (6,5) and (7,6) chirality. The technique offers the advantages of technical simplicity, scalability and non-destructive nature representing an important step toward the research, development and implementation of monochiral single-wall CNT tangible objects. ; The European Research Council (Grant Agreement - 259061). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

We have demonstrated fire-retardancy properties of a polymer matrix-free CNT film for the first time. As compared with classical fire-retardant materials such as Kevlar, Twaron or Nomex, the CNT film showed a spectrum of advantages. The material is lightweight, flexible and well-adherent to even the most complicated shapes. The results have showed that by using CNTs for fire-retardancy we can extend the operational time almost two-fold, what makes CNTs a much better protection than the solutions employed nowadays. We believe that among other great properties of CNT, their macroscopic assemblies such as CNT films show significant potential for becoming a fire protective coating, which exhibits high performance in not sustaining fire. ; The European Research Council (Grant Agreement - 259061). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

We report on the development of a method of formation of free-standing gold-carbon nanotube (CNT) composites. It is based on a quick and simple decoration of CNT films with the application of chloroauric aqueous solution. Flexible and conductive macroassemblies of any size and shape can be created with ease. Addition of as little as 1% of Au by weight allowed for reduction of resistance by more than a quarter. Higher Au doping resulted in further decrease of resistance, but not so significant. From the practical point of view, these composites are a new type of materials with high electrical conductivity, but also offer resistance to corrosion. ; The European Research Council (Grant Agreement - 259061). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

We have demonstrated that nanocarbon materials such as carbon nanotubes (CNTs) or graphene have an intrinsically hydrophilic nature. Addition of liquid hydrocarbons or polycyclic aromatic compounds, which are the common side-products of nanocarbon syntheses, turned the otherwise hydrophilic CNT films hydrophobic. The very small amount needed to cause this effect was not discernable by SEM or Raman spectroscopy and also it could be easily overlooked by other methods of analysis. Upon simple and rapid thermal desorption of these species we were able to fully recover the water affinity in these CNT networks. Without using any oxidizing agents the material remains hydrophilic for weeks having water contact angle of about 35°. The results pave the way towards implementation of low-dimensional nanostructures in the real life without disrupting their inherent properties. ; The Silesian University of Technology (Grant Agreement - 04/020/ RGJ18/0057). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799, UMO-2015/19/N/ST8/02184). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

This research details electronic and magneto-transport in unsorted and chirality-enriched carbon nanotube (CNT) films. By measuring electrical conductivity from 4 K to 297 K we were able to assign the governing mechanism of electronic transport. Fluctuation-Induced Tunnelling was in accordance with the obtained data and very well matched the underlying physics. We demonstrated how a change in the type of CNT to make the film affects its electrical performance. As the temperature was decreased down to cryogenic conditions, up to 56 fold increase in resistance was noted. Moreover, measurement of magnetoresistance (MR) revealed non-monotonic dependence on the applied magnetic field. Initial negative component of MR was eventually overpowered by the positive MR component as the field strength was increased beyond a certain threshold. ; The Silesian University of Technology (Grant Agreement - 04/020/RGH17/0050). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799, UMO-2015/16/S/ST3/00477). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

We have demonstrated that large diameter (1.8±0.4 nm) carbon nanotubes (CNTs) can be separated by means of the aqueous two phase extraction (ATPE). This rapid and convenient tool has enabled us to isolate fractions of particular CNT diameter distribution. We have shown how a range of parameters can be used to fine tune the characteristics of the isolated material. What is very interesting, by varying the pH of the medium, we have suppressed the extraction of low diameter CNTs and only large diameter CNTs were obtained. A number of other factors such as selected surfactant concentration steps, temperature or amount of starting CNT material have been found to have a significant effect on the end result of the CNT differentiation. The findings have provided us with more insight regarding the underlying mechanics of ATPE for processing polydisperse CNT mixtures. ; The Silesian University of Technology (Grant Agreement - 04/020/RGJ18/0057). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

The electronic properties of carbon nanostructures such as carbon nanotubes (CNTs) or graphene can easily be tuned by the action of various doping agents. We present an experimental study and numerical analysis of how and why metallic and semiconductive CNTs can be p-doped by exposing them to two interhalogens: iodine monochloride and iodine monobromide. Simple application of these compounds was found to reduce the electrical resistance by as much as 2/3 without causing any unfavorable chemical modification, which could disrupt the highly conductive network of sp2 carbon atoms. To gain better insight into the underlying mechanism of the observed experimental results, we provide a first principles indication of how interhalogens interact with model metallic (5,5) and semiconductive (10,0) CNTs. ; The European Research Council (Grant Agreement - 259061). The Interdisciplinary Centre for Mathematical and Computational Modelling at the University of Warsaw (Grant Agreement - G47-5). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

Carbon materials are among the most commonly used components of supercapacitor electrodes. Particularly, active carbons are recognized as cheap, available, and easily tailored materials. However, the carbon family, i.e. carbon products and carbon precursors, consists of many members. In this manuscript some of these materials, including laboratory scale-produced carbon gels, carbon nanotubes and carbonized materials, as well as industrial scale-produced graphites, pitches, coke and coal, were compared. Discussion was preceded by a short history of supercapacitors and review of each type of tested material, from early beginning to state-of-the-art. Morphology and structure of the materials were analyzed (specific surface area, pore volume and interlayer spacing determination), to evaluate their applicability in energy storage. Thermal analysis was used to determine the stability and purity. Finally, electrochemical evaluation using cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy was performed. Outcomes of each analytical technique were summarized in different sections. ; The Silesian University of Technology (Grant Agreement - 04/020/RGJ18/0057). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).

Stealth technology combines numerous means and techniques to be 'invisible' for opponents in a battle field. Since metals are the key construction materials of military vehicles, weapon and equipment, they can be targeted and detected by RAdio Detection And Ranging (RADAR) systems. Radar-Absorbent Materials (RAMs) – as crucial components of passive countermeasures in the modern-day military tactics – are used for absorption of electromagnetic waves. In the same time, mainly due to high electric conductivity, RAMs – accompanied by designed geometry of the objects they are incorporated into – can yield programmable reflection, multiple internal reflection and scattering towards Electromagnetic Interference (EMI) shielding. Nowadays, the latest achievements of nanotechnology have transformed stealth technology into an even more powerful tool. And among many nanomaterials, carbon nanotubes (CNTs) have arisen as one of the most promising active component of RAMs and EMI shielding materials. The unique sp2-derived macromolecular architecture equips CNTs with an exceptional combination of electromagnetic, mechanical and chemical properties. This review intends to summarize and critically evaluate the hitherto efforts in the production and applications of CNT nanocomposites/hybrid materials as key constructional civil and military elements, preferably as coatings, layers, films, textiles or panels, towards attenuation of the radio wave radiation. ; The Silesian University of Technology (Grant Agreement - BKM-530/RCH2/2016). The National Centre for Research and Development (Grant Agreement - TANGO1/266702/NCBR/2015). National Science Center, Poland (Grant Agreement - UMO-2015/19/P/ST5/03799). The European Union's Horizon 2020 research and innovation programme (Grant Agreement - 665778).