A research team led by Ouyang Wen'gen at Wuhan University (WHU), in collaboration with Shanghai Jiao Tong University, Zhejiang University, and the Chinese Academy of Sciences, has published a study in Science on densely packed homochiral carbon nanotube arrays.

The paper, titled Homochiral Carbon Nanotube van der Waals Crystals, presents a novel approach to assembling carbon nanotube structures with high precision.  

Schematic diagram of the carbon nanotube van der Waals crystal structure.

Carbon nanotubes, known for their exceptional electronic and thermal properties, hold great promise for next-generation electronic devices. However, fabricating high-density, well-aligned, and purely semiconducting nanotube arrays remains a significant challenge.  

The team developed a slip-assisted self-assembly growth technique, enabling the direct formation of high-density carbon nanotube arrays on an atomically smooth hexagonal boron nitride substrate. These arrays, formed through the repeated folding of a single long nanotube, exhibit outstanding electrical performance at room temperature, with carrier mobility reaching 2000 cm²V⁻¹s⁻¹, a current-carrying capacity exceeding 6.5 mA/mm, and an on/off ratio of 10⁷.  

Growth, performance characterization, and mechanism analysis of carbon nanotube arrays.

The study also unveils the dual driving forces behind nanotube array formation and introduces a "bending energy–interface adhesion energy" competition model to explain the creation of closed-loop structures. This breakthrough paves the way for high-performance carbon-based nanoelectronic chips and advances the controlled synthesis of novel van der Waals (vdW) materials.

Link to paper: https://www.science.org/doi/10.1126/science.adu1756