A study on temperature dependency and in situ observation of domain structure in Langmuir layers of stearic acid/gamma-Fe2O3 nanoparticle complex at the air/water interface

The Langmuir monolayer behavior of a stearic acid/gamma -Fe2O3 nanoparticle complex at the air/water interface have studied at different subphase temp erature. The subphase was pure water and an aqueous colloidal solution of g amma -Fe2O3 nanoparticles with an average diameter of 81 +/- 12 Angstrom. T he formation and stability of Langmuir monolayer at different subphase temp eratures were measured with pressure-area isotherm curve of stearic acid on a subphase of pure water and gamma -Fe2O3 nanoparticle hydrosol. In situ d omain structure and molecular orientation of stearic acid/gamma -Fe2O3 nano particle complex at the air/water interface were measured with Brewster ang le microscopic (BAM) image and surface potential at different subphase temp eratures. (C) 2001 Elsevier Science B.V. All rights reserved.