Premium
Kinetically Controlled Synthesis of Hexagonally Close‐Packed Cobalt Nanorods with High Magnetic Coercivity
Author(s) -
Soumare Yaghoub,
Garcia Cécile,
Maurer Thomas,
Chaboussant Grégory,
Ott Frédéric,
Fiévet Fernand,
Piquemal JeanYves,
Viau Guillaume
Publication year - 2009
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.200800822
Subject(s) - materials science , coercivity , nanorod , cobalt , crystallinity , chemical engineering , carboxylate , polyol , dispersity , template , ferromagnetism , phase (matter) , nanotechnology , composite material , metallurgy , polymer chemistry , organic chemistry , condensed matter physics , chemistry , physics , polyurethane , engineering
High‐quality monodisperse metallic cobalt nanorods are obtained by the reduction of carboxylate salts of Co II in 1,2‐butanediol using a rapid, simple, and solid‐template‐free procedure. In this polyol process, particle shape can be controlled via the growth rate, which depends on three parameters: i) the nature of the cobalt carboxylate, ii) the temperature ramp, and iii) the basicity of the medium. Cobalt in the hexagonally close‐packed phase favored the growth of anisotropic particles. Magnetic measurements of the cobalt nanorods indicate they are ferromagnetic at room temperature. They have a very high coercivity of 9.0 kOe at 140 K, much higher than that observed for wires prepared with solid templates. This can be attributed to their small mean diameter and high crystallinity.