The size of the primary particle of ND obtained by the detonation technique is suitable for biomedical studies, the detonation products must be extensively purified. Depending on the materials and matrices present during their production, detonation NDs may contain oxides and carbides, including those of iron, chromium, silicon, calcium, copper, potassium, titanium, and sulfur, as well as carbon soot. To remove surface metallic impurities, NDs are treated with classic acid treatments containing sulfuric acid and its mixtures with nitric acid or potassium dichromate. A combination of hydrofluoric acid and nitric acid was also used to remove metal contaminants from the particles. The oxidation and subsequent removal of sp2 bonded carbon structures, present in both amorphous and graphitic form, is achieved through the use of liquid oxidants such as sodium peroxide, a mixture of chromium trioxide and sulfuric acid or a mixture of nitric acid and hydrogen peroxide7. The thermal oxidation process uses temperatures of 400°C–430°C to allow oxidation of sp2-bonded carbon species in air, with negligible alterations in sp3-bonded carbon structures. These temperature requirements for the selective oxidation of sp2-bonded carbon species were confirmed by the authors. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay Oxidation of NDs at high temperature using ozone-containing air is another approach that involves major removal of sp2 hybridized carbon structures. Ozone air treatment, also known as "gas phase treatment", is environmentally friendly and efficient, since the purification of NDs is achieved without the use of corrosive liquid oxidants24. Although the size, shape, and surface properties of NDs are determined by the nature of the explosion and purification conditions, their basic structure follows a core-and-shell model. The carbon of the diamond forms the inert core and the surface shell is partially containing graphitic structures. Furthermore, a wide variety of functional groups such as carboxyl, hydroxyl, lactone, anhydride, ketone, and ether can be present on the surface of these ND particles. X-ray diffraction is one of the most used techniques to characterize NDs, also in terms of size, structure and composition. After annealing the NDs at 1500°C for 10 minutes under vacuum, the diamond X-ray diffraction peak disappears with the exposure of the sp2 carbon structure peak. The crystal lattice parameters and quality of NDs can vary depending on the synthesis conditions, as determined by X-ray diffraction studies199. Please note: this is just a sample. Get a custom paper from our expert writers now. Get a Custom EssayThe economical large-scale production of detonation NDs gives a major boost to technological applications. For example, the anti-friction properties of NDs and their soot make them ideal candidates as wear protective additives. The stability of these particles at extreme temperatures has led to applications in composite manufacturing. The large surface area of ​​NDs is suitable for adsorbing biomolecules, presenting them as an attractive material for isolating proteins and pathogenic microorganisms, as shown in the table200.