Modification of Diamond Particles for Improved Dispersion in Liquid Phase

Abstract

Photochemical modification of diamond was carried out by covalently bonding the radicals of 2-propanol-2-yl [(CH₃)₂C^*OH] on the surface of diamond, which were produced by the photochemical disintegration of 2-hydroxy-2-methyl-1-phenyl-1-propanone irradiated by ultraviolet rays. A dispersion of diamond was prepared in acetone with the subsequent addition of 2-hydroxy-2-methyl-1-phenyl-1-propanone which acted as photoinitiator. This mixture was put under irradiation with UV light for the generation of free radicals from 2-hydroxy-2-methyl-1- phenyl-1-propanone. These free radicals were introduced onto the surface of diamond and improved the dispersion in liquid phase. The modified diamond was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, thermogravimetric analysis, thermogravimetric analysis-mass spectrometry and scanning electron microscopy. The scanning electron microscopy and dispersibility data demonstrated that the surface modification of diamond helped to improve its dispersibility in common organic solvents as well as the functional behaviour of its surface which may be useful in diagnosis/treatment of various diseases.