Sintering prevention and phase transformation of FePt nanoparticles

Two approaches attempted to overcome FePt nanoparticle sintering during the transformation to the high coercivity L 1(0) phase, which currently limits the use of these nanoparticles in data storage media. High-pressure treatment of dilute nanoparticle solutions failed to prevent sintering due to surfactant decomposition above 360 degreesC. By pre-annealing nanoparticle monolayers to decompose the surfactant, and then coating with an immiscible SiO2 matrix, sintering was prevented with annealing temperatures up to 700 degreesC. (C) 2004 Elsevier B.V. All rights reserved.