## 1 Introduction  
Carbon nanotubes (CNTs) are macromolecules whose discovery, arguably attributable to Professor [PERSON] [1, 2], has provided heretofore unimagined potential for engineering applications. CNTs have garnered immense research interest because of their unique structure and physical properties [3, 4, 5]. At the nanoscale level, they exhibit very high strength and electrical and thermal conductivities [6, 7, 8]. Single-walled CNTs have been shown to have a Young's modulus of greater than 1 TPa [9], with an electrical resistivity as low as \(3\times 10^{-7}\)\(\Omega\) m [10] and a thermal conductivity as high as 3000 Wm K\({}^{-1}\)[11, 12]. Furthermore, CNTs have been reported to have a large ampacity compared with metals, suggesting their untapped potential in electronics [13]. In addition, the heat dissipation capabilities of CNT arrays as thermal interfaces have been demonstrated [14]. Several researchers have attempted to prepare CNT/Cu composites with varying degrees of success [15, 16, 17], but in order to take advantage of CNTs' physical properties, significant efforts have been devoted to growing CNTs on metal substrates in order to achieve chemical bonding [18, 19, 20]. Chemical vapor deposition (CVD) has been adopted as the most effective and suitable method for synthesizing vertically aligned CNTs on metals, but traditional CVD requires temperatures above 650 \({}^{\circ}\)C to produce high-quality CNTs. It has been reported that high temperatures negatively affect the lifetime of the catalyst nanoparticles by promoting catalyst ripening, carbide formation, alloying, and coarsening [21, 22]. Both the essential necessity of an Al\({}_{2}\)O\({}_{3}\) support during synthesis and the negative effect of its dielectric nature on limiting the electron transport process have been demonstrated [23]. High-density CNT arrays that can support interconnections have been developed [24; 25; 26]. However, the creative approaches required to synthesize CNTs directly on metal substrates, including Cu, Al, Ti, Ta, and stainless steel, demonstrate the challenges involved in growing high-quality CNTs [18; 26; 27; 28]. In addition, experimental metal alloy combinations for interfacing through traditional soldering have been reported [29; 30]. Although synthesis of CNTs at temperatures as low as 350 \({}^{\circ}\)C have been accomplished, increasing their density has shown itself to be a challenge [31; 32; 33]. In general, interfacing metals with organic molecules or solvents is a major challenge in material development, especially for CNTs because of issues such as the nanotube dimensions, orientation, and wettability. In most efforts to grow CNTs directly on metal substrates, the CNT quality has been compromised by attempts to reduce the temperature and oxide catalyst support thickness [27; 28]. Other interfacing approaches such as the self-assembly of monolayers [14; 34], soldering [29; 30], colloidal metallic pastes [35], and electrodeposition have also been employed, but they all have shown limitations. Despite almost three decades of intense CNT research, most synthesis methods have failed to meet expectations due to challenges associated with CNT synthesis, controlling CNT type, chirality and diameter [36; 37; 38; 39]. unsatisfactory results have been achieved for several electrical and thermal applications based on current CNT assemblies. One reason for this poor performance includes the ability to assemble CNTs into macroscopic fibers and films with similar properties [40; 41], as well as the assumption that traditional macroscopic contact interfacing methods are sufficient to connect most carbon nanomaterials to metal surfaces. High thermal and electrical interface resistances have been reported between CNTs and their contacts, owing to weak adhesion of the nanoscale paths [14; 34; 42; 43].