Electrical properties of boron-doped MWNTs synthesized by hot-filament chemical vapor deposition

TL;DR

This study reports the synthesis of boron-doped multiwalled carbon nanotubes via hot-filament chemical vapor deposition and investigates their structural and electrical properties, revealing high resistivity likely due to plasma-induced defects.

Contribution

It introduces a method for synthesizing boron-doped MWNTs using hot-filament CVD and evaluates their structural and electrical characteristics.

Findings

Boron doping was successfully incorporated into MWNTs.

Resistivity increased with decreasing temperature, indicating semiconducting behavior.

Defects from plasma may contribute to high resistivity.

Abstract

We have synthesized a large amount of boron-doped multiwalled carbon nanotubes (MWNTs) by hot-filament chemical vapor deposition. The synthesis was carried out in a flask using a methanol solution of boric acid as a source material. The scanning electron microscopy, transmission electron microscopy, and micro-Raman spectroscopy were performed to evaluate the structural properties of the obtained MWNTs. In order to evaluate the electrical properties, temperature dependence of resistivity was measured in an individual MWNTs with four metal electrodes. The Ramman shifts suggest carrier injection into the boron-doped MWNTs, but the resistivity of the MWNTs was high and increased strongly with decreasing temperature. Defects induced by the plasma may cause this enhanced resistivity.