H 0172 (OTTO) Hexylphosphonic acid, 95% Cas 4721-24-8 - used in the manufacturing of nanoparticles such as quantum dots, nano-metals and nano-ceramics. H 0172 (OTTO) Hexylphosphonic acid, 95% Cas 4721-24-8 - used for coating of many materials, including nanoparticles by condensed hydrophobic monolayers.