Electrodeposited Cu/buckypaper composites with high electrical conductivity and ampacity

Corrosion behaviour of cast and deformed copper-carbon nanotube composite wires in chloride media

“…30 cm) could be deposited without a sample holder, simply by gluing a small piece of PVC plastic at the bottom of the yarn to hold the sample straight in an otherwise similar setup. The electrolytes used in electrochemical deposition were aqueous based copper sulfate baths in similar concentrations as often applied in electrodeposition of copper on carbon materials and in industrial electroplating (Paunovic & Schlesinger, 2006;Sundaram et al, 2017a;Tao et al, 2017;Chen et al, 2018a;Kim et al, 2018). The following electrochemical deposition electrolytes were used: Electrolyte I: 0.8 M CuSO4•5H2O and 0.4 M H2SO4 (Publication I) Electrolyte II: 0.6 M CuSO4•5H2O, 0.8 M H2SO4 and 0.1mM NaCl (Publication II) Electrolyte III: 0.6 M CuSO4•5H2O and 0.9 M H2SO4 (Publication III) Electrolyte IV: 0.1 M CuSO4•5H2O, 3 M H2SO4, 1.0 mM NaCl and industrial accelerator CG 2001 Additive (Shipley) 0.8 ml/l Galvanostatic deposition (Publication I, II and III) and potentiostatic oxidation (Publication III) techniques were utilized in production of CNT-Cu composites.…”

“…These factors play a key role in how such a structure, including different types of fibers, yarns and films, will be wetted by the electrolyte when immersed in the electrochemical cell. Different authors attempt to overcome the issue of non homogeneous deposition of CNT material by various methods including using additives in aqueous electrolytes (e.g., Tao et al (2017)), using organic electrolytes (e.g., Subramaniam et al 2013;Sundaram et al 2018), oxidizing the CNT material before deposition (e.g., Publication III, Chen et al (2018a)) and utilizing very low deposition current density (e.g., Publication I-III, Subramaniam et al (2013); Tao et al (2017); Sundaram et al (2018)).…”

“…Production and properties of CNT based coatings on Cu, such as the one shown in Figure 7c are rarely reported, except for some exceptions (see, e.g., Duan et al, 2017). Due to the high density of some CNT macrostructures, another typical form of CNT-Cu produced by different Cu deposition methods, such as electrodeposition (Chen et al, 2018a) and physical vapour deposition (PVD) (Han et al 2018) is shown in Figure 7d. The commonly accepted challenges in producing high quality copper matrix CNT composites with enhanced properties beyond pure Cu are related to (i) the quality and stability of CNTs, (ii) the bond strength and interface quality between CNTs and the copper matrix and (iii) obtaining a homogenous dispersion and orientation of CNTs throughout the copper matrix (Hjortstam et al, 2004;Bakshi et al, 2010;Zhao et al, 2016).…”

“…Another option often utilized is grafting some functional groups on the nanotube surfaces. This can be achieved either by polymer wrapping or by oxidation, to form carboxyls and other oxygen containing functional groups (Chen et al, 2018a;Firkowska et al, 2011).…”

“…Conversely, the interfacial oxygen can also act as a barrier for electron and phonon transport, which would affect the thermal and electrical properties adversely (Kim et al, 2008). Despite this, some experimental reports have shown higher thermal conductivity, specific electrical conductivity and ampacity in CNT-Cu composites when the CNTs have been functionalized with oxygen containing groups (e.g., Yang et al, 2008;Firkowska et al, 2011;Cho et al, 2012;Chen et al, 2018a). Similar improvements for mechanical properties have been obtained for CNT-Cu with functionalized nanotubes (e.g., Cha et al, 2005;Kim et al, 2007Kim et al, , 2008Kim et al, , 2011.…”