title: Wet-chemical synthesis and properties of CoPt and CoPt3 alloy nanoparticles.
abstract: Surface-protected, air-stable nanoparticles of CoPt and CoPt3 were prepared by thermal decomposition/reduction of organometallic precursors with a long-chain aliphatic diol, also known as the polyol process. Particles 3 nm in diameter showed ferromagnetic behavior up to 350 K (Hc = 65 Oe at T = 300 K; Hc = 410 Oe at T = 5K) and underwent a disordering-ordering phase transformation after annealing that resulted in an increase in coercivity (Hc = 170 Oe at T = 300 K; Hc = 2000 Oe at T = 5 K).
authors.affiliation: Forschungszentrum Karlsruhe GmbH, Institut für Nanotechnologie, Postfach 3640, D-76021 Karlsruhe, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Frommen
authors.forename: Harald
authors.initials: H
authors.lastname: Rösner
authors.forename: Dieter
authors.initials: D
authors.lastname: Fenske
mesh_terms: D000497:Alloys / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification; D003460:Crystallization / Q000379:methods*; D006358:Hot Temperature; D008280:Magnetics; D008422:Materials Testing / Q000379:methods; D008863:Microspheres; D008968:Molecular Conformation; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D010316:Particle Size; D011208:Powders; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D017155:Wettability; D014961:X-Ray Diffraction
chemical_list: D000497:Alloys; D011208:Powders; D012996:Solutions; C477450:cobalt platinum alloy