Critical challenges and advances in the carbon nanotube–metal interface for next-generation electronics

Next-generation electronics can no longer solely rely on conventional materials; miniaturization of portable electronics is pushing Si-based semiconductors and metallic conductors to their operational limits, flexible displays will make common conductive metal oxide materials obsolete, and weight reduction requirement in the aerospace industry demands scientists to seek reliable low-density conductors. Excellent electrical and mechanical properties, coupled with low density, make carbon nanotubes (CNTs) attractive candidates for future electronics. However, translating these remarkable properties into commercial macroscale applications has been disappointing. To fully realize their great potential, CNTs need to be seamlessly incorporated into metallic structures or have to synergistically work alongside them which is still challenging. Here, we review the major challenges in CNT–metal systems that impede their application in electronic devices and highlight significant breakthroughs. A few key applications that can capitalize on CNT–metal structures are also discussed. We specifically focus on the interfacial interaction and materials science aspects of CNT–metal structures.