Nanodiamond coating by polyethylenimine for optical limitation

Abstract

Polyethylenimine (PEI) is used to elaborate detonation nanodiamonds coated with a polymer material. Evolution of the nanodiamonds surface charge depending on the PEI concentration is revealed by a zeta potential study. While the surface charge of the nanodiamond is negative due to its oxygenated functional groups, the cationic polymer allows reversing it to a positive one. Spectroscopy characterizations are used to investigate the PEI interaction with the nanodiamonds and to estimate the very small thickness of the PEI layer on the nanodiamonds surface. The oxygenated functional groups of the nanoparticles interact electrostatically with the PEI amine groups. The good performances of the non-linear optical properties of this material are demonstrated at a wavelength of 1064 nm.