Effect of sodium oleate adsorption on the colloidal stability and zeta potential of detonation synthesized diamond particles in aqueous solutions

Surface properties of a nanometer-scale diamond prepared from detonation synthesis were discussed and the dispersion of this nanodiamond (ND) in aqueous solutions was actualized utilizing the method of mechanochemical treatment (MCT). While preparing a stable suspension in alkaline aqueous media, the addition of an anionic surfactant, sodium oleate (SO), can increase the absolute value of ND surface zeta potential, strengthen the electrostatic stabilization and improve the hydrophilicity of the particles. Mechanisms of the surfactant adsorption on ND surface were investigated using Fourier Transform Infrared Spectroscopy (FTIR) and the measures of particle size, surface potential and adsorption capacity of SO on particle surface. Interactions of electrostatic, hydrogen bonding, hydration, and hydrophobic have influence on the adsorption behavior of SO. Dispersion efficiency and colloidal stability behavior of ND particles are dominated markedly by the electrostatic, hydration and hydrophobic interactions among the modified particles.