Fluorescence and Physico-Chemical Properties of Hydrogenated Detonation Nanodiamonds

Hydrogenated detonation nanodiamonds are of great interest for emerging applications in areas from biology and medicine to lubrication. Here, we compare the two main hydrogenation techniques-annealing in hydrogen and plasma-assisted hydrogenation-for the creation of detonation nanodiamonds with a hydrogen terminated surface from the same starting material. Synchrotron-based soft X-ray spectroscopy, infrared absorption spectroscopy, and electron energy loss spectroscopy were employed to quantify diamond and non-diamond carbon contents and determine the surface chemistries of all samples. Dynamic light scattering was used to study the particles' colloidal properties in water. For the first time, steady-state and time-resolved fluorescence spectroscopy analysis at temperatures from room temperature down to 10 K was performed to investigate the particles' fluorescence properties. Our results show that both hydrogenation techniques produce hydrogenated detonation nanodiamonds with overall similar physico-chemical and fluorescence properties.