Surface phase diagram and thermodynamic stability of functionalisation of nanodiamonds

Surface functionalisation has been widely applied to nanodiamonds, as well as other nanomaterials, with the aim of promoting stability (saturation of dangling bonds) and expanding applications. Since nanodiamonds are a promising candidate for applications in biology and nanomedicine, careful control of the stability and homogeneity of the surface functionalisation is crucial. Here, the facet-dependent thermodynamic stabilities of individual diamond nanoparticles functionalised with hydrogen, oxygen, and hydroxyl have been systematically examined using electronic structure computer simulations. Based on these results, phase diagrams for the functionalised nanodiamonds have been established, mapping the stability as a function of the partial pressures of the participating species.