Effect of oxidizing treatment on surface modification of detonation nanodiamond

Detonation nanodiamond (DND) possesses high hardness, high thermalconductivity, good insulation, and fine grains, offering a wide range of applicationprospects. However, DND particles typically exist in an agglomerated state due to theirhigh specific surface area and high surface activity caused by the detonation reactionThis often leads to the loss of many of its advantages as a nano-powder during actualuse, preventing the full utilization of its superior properties. In this study, air oxidationwas adopted to investigate the dispersion and purification of DND. DND samples weretreated with air oxidation at different temperatures using a muffle furnace, andcharacterized using X-ray diffraction (XRD), inductively coupled plasma (ICP), Ramanspectroscopy, infrared spectroscopy, and other techniques. The results showed that at 450 ℃, SP ² amorphous carbon and CH functional groups in DND were effectively removed, improving the purity of DND and reducing impurity content by 30% asdetermined by ICP, The average particle size of DND was approximately 15 nm, with adispersing effect improved by 92.5% compared to unoxidized DND. Air oxidation at 450 ℃ selectively removes non-diamond carbon without losing the diamond phase.