How to efficiently isolate multiple size ranges of oxidized or hydrogenated milled nanodiamonds†

Nanodiamonds exhibit various properties, such as surface reconstruction, electrostatic potentials of facets, and thermal, fluorescence, or quantum characteristics, which are dependent on their size. However, the synthesis method can lead to significant size polydispersity, particularly in nanodiamonds obtained from milling (MND). Therefore, it is essential to efficiently sort MND by size to ensure uniformity and optimize their properties for biomedical, sensing or energy applications. This method successfully isolates nanodiamonds into three distinct size ranges: approximately 10 nm for the smallest, 25 nm for the intermediate, and 35 nm for the largest. The protocol was then extended to hydrogenated MND from the same source, resulting in the separation of similar size populations.