The supramolecular approach to the phase transfer of carboxylic calixresorcinarene-capped silver nanoparticles

Abstract

© 2017 Elsevier B.V.The octacarboxylic derivative of tetrapentylcalix[4]resorcinarene (1) was used as stabilizer for preparation of silver nanoparticles (AgNPs) hydrosol. The calixresorcinarene-capped nanoparticles Ag@1 are stably dispersed in an aqueous colloid solution and have an average diameter of 4–6 nm (TEM). The interaction of the macrocycle 1, possessed the receptor properties, with the cationic surfactant cetyltrimetylammonium bromide (CTAB) leads to the hydrophobization of AgNPs hydrosol. It was shown, that macrocycle 1 in its individual solution forms the hydrophobic associate with 8 mol of CTAB (1H NMR, 2D NOESY). Various and complicated influence of CTAB/macrocycle molar ratio on the hydrophobization of AgNPs and their transfer into organic phase was demonstrated. The initial Ag@1 and modified Ag@1-CTAB were characterized by UV-vis and FTIR spectroscopy, DLS, and TG/DSC methods It was shown that the efficiency of water/organic phase transfer depends on the macrocycle/surfactant molar ratio. The presented supramolecular approach can be useful to form the ordered nanostructures through supramolecular modification and self-organization of hybrid metal nanoparticles.