# Topological Defects in Carbon Matrix are Efficiently Constructed by Joule Thermal Shock for Catalyzing the Growth of Carbon Nanotubes

## TL;DR

This study introduces a method using Joule thermal shock to create topological defects in carbon, which catalyze the growth of carbon nanotubes.

## Contribution

A new method for efficiently creating topological defects in carbon using Joule thermal shock is proposed.

## Key findings

- Joule thermal shock efficiently constructs topological defects in carbon matrices.
- Topological defects activate carbon source molecules through electron transfer.
- Defects induce self-assembly processes that lead to carbon nanotube growth.

## Abstract

This study aims to establish a simple and efficient method for preparing topological defect carbon (TDC) and reveal its catalytic mechanism for the growth of carbon nanotubes (CNTs). TDC is prepared using N‐doped carbon as a precursor through multiple Joule thermal shock treatments, and the efficiency of this method in constructing topological defects in the carbon matrix is confirmed by multi‐dimensional characterization. Subsequently, the TDC catalyzed the growth of CNTs, and a possible catalytic growth mechanism based on the synergistic interaction of multiple defects is proposed. The mechanism proposes that the carbon source molecules are activated through electron transfer from pentagonal topological defects and the slight assistance of other defects, and then the activated molecules form a metastable carbon layer by self‐assembling, combined with dehydrogenation rearrangement according to the defect curvature, which further self‐assembles to achieve the growth of CNTs based on the edge activity of the carbon layer. Therefore, this study not only brings new perspectives to clarify the growth mechanism of specialty carbon‐catalyzed CNTs, but also provides an efficient research and development platform for this type of specialty carbon catalysts.

The Joule thermal shock technique ensures the efficient construction of topological defects in the carbon matrix because the instantaneous cooling suppresses the graphitization rearrangement of the heteroatom removal sites. This topological defect carbon can activate carbon source molecules by electron transfer, and further grow into carbon nanotubes based on the self‐assembly process under defect induction.