Copper/carbon nanotube composites: research trends and outlook

Abstract

We present research progress made in developing copper/carbon nanotube composites (Cu/CNT) to fulfil a growing demand for lighter copper substitutes with superior electrical, thermal and mechanical performances. Lighter alternatives to heavy copper electrical and data wiring are needed in automobiles and aircrafts to enhance fuel efficiencies. In electronics, better interconnects and thermal management components than copper with higher current- and heat-stabilities are required to enable device miniaturization with increased functionality. Our literature survey encouragingly indicates that Cu/CNT performances (electrical, thermal and mechanical) reported so far rival that of Cu, proving the material's viability as a Cu alternative. We identify two grand challenges to be solved for Cu/CNT to replace copper in real-life applications. The first grand challenge is to fabricate Cu/CNT with overall performances exceeding that of copper. To address this challenge, we propose research directions to fabricate Cu/CNT closer to ideal composites theoretically predicted to surpass Cu performances (i.e. those containing uniformly distributed Cu and individually aligned CNTs with beneficial CNT–Cu interactions). The second grand challenge is to industrialize and transfer Cu/CNT from lab bench to real-life use. Toward this, we identify and propose strategies to address market-dependent issues for niche/mainstream applications. The current best Cu/CNT performances already qualify for application in niche electronic device markets as high-end interconnects. However, mainstream Cu/CNT application as copper replacements in conventional electronics and in electrical/data wires are long-term goals, needing inexpensive mass-production by methods aligned with existing industrial practices. Mainstream electronics require cheap CNT template-making and electrodeposition procedures, while data/electrical cables require manufacture protocols based on co-electrodeposition or melt-processing. We note (with examples) that initiatives devoted to Cu/CNT manufacturing for both types of mainstream applications are underway. With sustained research on Cu/CNT and accelerating its real-life application, we expect the successful evolution of highly functional, efficient, and sustainable next-generation electrical and electronics systems.

Carbon Nanotube‐Reinforced Aluminum Matrix Composites

“…Two major CNT/Cu fabrication routes: a) PM [31] and b) electrodeposition. [32] between the metal matrix and reinforcement was reported by this method. Alekseev et al [38] investigated the effect of CNTs on the mechanical properties of cast Al, grade A5.…”

“…Started in 1928 in an automotive company in the USA, the electrochemical deposition was instigated by depositing graphite on copper plate, as shown in Figure 3b. [32] Initially, this was used in coatings especially the wear-resistant coatings in the field of aerospace and automotive applications. The thickness of the coatings is usually in the order of micrometer.…”

Understanding the Mechanical and Conductive Properties of Carbon Nanotube Fibers for Smart Electronics

“…Specially, in electronics, better interconnects and thermal management components than copper with higher current‐ and heat‐stabilities are required to enable device miniaturization with increased functionality . Metallic CNTs have been identified as a possible interconnect material, owing to their excellent electrical properties in terms of conductivity, ampacity, and high frequency characteristics.…”

Self-lubricating Cu-MWCNT coatings deposited from an ecofriendly glutamate-based electrolyte

“…Moreover, a considerable decrease in the wear rate of both Ni-P [4] and Ni [5] coatings was observed, ascribed to the presence of loose CNTs between the surfaces in contact, released during initial stages of the wear test, which prevent their intimate contact. On the other hand, Cu-CNT composites have been the focus of several investigations for a while [4,[23][24][25][26][27][28][29][30][31]. Pure copper coatings have been mainly used for protective and decorative purposes due to their good corrosion resistance and appearance, as well as in electrical or electronic applications due to copper's high electrical and thermal conductivities.…”

“…Pure copper coatings have been mainly used for protective and decorative purposes due to their good corrosion resistance and appearance, as well as in electrical or electronic applications due to copper's high electrical and thermal conductivities. However, this is a soft and heavy material [31], and thus it is not suitable for novel applications in which lightweight and high strength functional materials (e.g. with high thermal stability and high electrical conductivity) are required [30].…”