# Electrical Transport Properties of Polycrystalline and Amorphous TiO2 Single Nanotubes

## TL;DR

This study investigates the electrical transport properties of TiO2 nanotubes in amorphous and polycrystalline phases, revealing non-linear conduction behavior and conductance enhancement through ion irradiation, with phase confirmed by Raman spectroscopy.

## Contribution

It provides new insights into the electrical behavior of TiO2 nanotubes and demonstrates conductance enhancement via ion irradiation, advancing understanding of their transport mechanisms.

## Key findings

- Non-linear I-V characteristics explained by fluctuation induced tunneling model.
- Conductance enhancement observed in anatase nanotubes after ion irradiation.
- Raman spectroscopy confirms phase and phonon confinement effects.

## Abstract

The electrical transport properties of anodically grown TiO2 nanotubes was investigated. Amorphous nanotubes were anodically grown on titanium foil and transformed through annealing into the anatase phase. Amorphous and polycrystalline single nanotubes were isolated and contacted for measurements of the electrical resistance. Non-linear current-voltage characteristics were explained using the fluctuation induced tunneling conduction model. A clear enhancement of the conductance was induced in an insulating anatase nanotube through low-energy Ar/H ion irradiation. Confocal Raman spectroscopy shows that the annealed samples were in anatase phase and a blueshift due to phonon confinement was observed.