Production of Metal-free Diamond Nanoparticles

TL;DR

This paper demonstrates methods for producing high-quality, metal-free diamond nanoparticles, highlighting how milling materials influence contamination and purity, which is crucial for quantum applications.

Contribution

It introduces controlled production techniques for metal-free diamond nanoparticles and analyzes how milling materials affect contamination levels.

Findings

Milling with tempered steel leaves iron oxide contamination.

Using SiN reduces metal contamination but increases non-diamond carbon.

Removing metal impurities enables customized diamond nanoparticles for advanced applications.

Abstract

In this paper, the controlled production of high quality metal-free diamond nanoparticles is demonstrated. Milling with tempered steel is shown to leave behind iron oxide contamination which is difficult to remove. Milling with SiN alleviates this issue but generates more non diamond carbon. Thus the choice of milling materials is critically determined by the acceptable contaminants in the ultimate application. The removal of metal impurities, present in all commercially available nanoparticles, will open new possibilities towards the production of customised diamond nanoparticles, covering the most demanding quantum applications.