The growth mechanism of CuO nanowires synthesized by the thermal oxidation method

TL;DR

This paper investigates the growth mechanism of CuO nanowires synthesized by thermal oxidation, providing evidence that vapor-solid growth is the dominant process based on morphological and structural analysis.

Contribution

The study clarifies the growth mechanism of CuO nanowires, demonstrating that vapor-solid growth explains their formation better than diffusion mechanisms.

Findings

Nanowires grow during cooling with annealing ambient

Presence of screw dislocations supports VS growth

Kinetic analysis aligns with vapor-solid growth mechanism

Abstract

Large-scale CuO nanowires are commonly synthesized by the thermal oxidation method. However, the growth mechanism remains controversial between diffusion growth mechanism and vapor-solid (VS) growth mechanism. In this study, we investigated the morphology and atomic structure of the CuO nanowires by electron microscopes to clarify the growth mechanism. We found that they were grown with the annealing ambient during the cooling process and there were screw dislocations in the nanowires. These features indicate that the VS growth mechanism is applicable to explain the growth of the CuO nanowires. In addition, the kinetic consideration also supports the VS growth mechanism.