The role of carbon nanotubes in modern electrochemical energy storage: A comprehensive review

The quest for sustainable energy storage solutions is more critical than ever, with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources. Carbon nanotubes (CNTs), with their exceptional electrical conductivity and structural integrity, are at the forefront of this endeavor, offering promising avenues for the advancement of electrochemical energy storage (EES) devices. This review provides an in-depth analysis of the synthesis, properties, and applications of CNTs in the context of EES. We explore the evolution of CNT synthesis methods, including arc discharge, laser ablation, and chemical vapor deposition, and highlight the recent developments in metal-organic framework derived CNTs and a novel CNT aggregate with three-dimensional ordered macroporous structure. The review further examines the role of CNTs in enhancing the performance of various EES devices such as lithium-ion batteries, lithium-metal batteries, lithium-sulfur batteries, sodium batteries, flexible batteries, and supercapacitors. We underscore the challenges that remain, including the scalability of CNT synthesis and the integration of CNTs in electrode materials, and propose potential solutions and future research directions. By drawing on our group’s research and the latest findings in the field, this review presents a forward-looking perspective on the pivotal role of CNTs in shaping the future of sustainable EES technologies.