Shape-controlled solution synthesis of ferromagnetic copper chromium selenide (CuCr2Se4) crystallites

Ferromagnetic crystallites of chalcospinel CuCr2Se4 have been synthesized in solution via a one-pot thermal decomposition of metal-acetyl aceton ate precursors in tri-n-octylamine. The reaction is carried out at temperatures of 300-350 degrees C in the presence of the cation precursor H2Se, formed in situ by the reduction of Se powder in beta-sitosterol. Good control on the growth rate and the shape of the crystallites is obtained by varying the reaction time and temperature, and the concentration of Se. The crystallites are ferromagnetic at room temperature and under optimal synthesis conditions exhibit a low temperature magnetic moment of about 2.3 mu(B) per Cr, which is close to reported value for the bulk. (c) 2007 Elsevier B.V. All rights reserved.