Chem. Mater. 2008, 20, 1367–1375
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Soluble Ligand-Stabilized Cyano-Bridged Coordination Polymer Nanoparticles Elena Chelebaeva,†,‡ Yannick Guari,*,† Joulia Larionova,*,† Alexandre Trifonov,‡ and Christian Guérin† Institut Charles Gerhardt, UMR 5253, Chimie Moléculaire et Organisation du Solide, UniVersité Montpellier II, Place E. Bataillon, 34095 Montpellier, France, and G. A. RazuVaeV Institute of Organometallic Chemistry of the Russian Academy of Science, Tropinina 49, GSP-44S, 603950 Nizhny NoVgorod, Russia ReceiVed July 19, 2007
Size controlled organic phase soluble cyano-bridged bimetallic coordination polymer nanoparticles made of Mn+ and [M′(CN)6]3- (with Mn+ ) Mn2+, Ni2+, Fe2+, Eu3+, Tb3+, Sm3+ and M′ ) Fe3+, Cr3+) were synthesized by using oleic acid and trialkylamines or a triarylamine as stabilizing agents. The obtained nanoparticles were studied by transmission electronic microscopy (TEM), infrared and electronic spectroscopy, X-ray diffraction, and magnetic measurements. These analyses revealed the formation of spherical metallic cyano-bridged nanoparticles with sizes in the range of 2–5 nm depending on the nature of the metal ion used. The magnetic studies of these colloidal solutions revealed the presence of a pure superparamagnetic regime for the nanoparticles based on [Cr(CN)6]3- and a collective regime caused by weak dipolar interparticle interactions for the nanoparticles based on [Fe(CN)6]3-.
Introduction The synthesis and study of nanometer-scaled particles have attracted a great deal of attention in the recent years because of their fundamental interest and their potential applications.1 Because of the very important ratio of surface/core atoms and confinement effects, metal-containing nanometer-scaled materials often exhibit the appearance of new interesting sizedependent physical and chemical properties, which cannot be observed in their bulk analogues.2 For this reason, nanosized materials are interesting candidates for applications in many fields, including electronics, catalysis, separation, biology, medical imagery, and others.3 However, the synthesis of such nanosized objects is rendered difficult because of the need of size, shape, phase purity, and surface state control. Among numerous investigated nanosized objects of different types,4 coordination polymer nanoobjects and especially magnetic cyano-bridged metallic coordination polymer nanoparticles attracted a great deal of interest in the past five years.5–12 A pioneering work on the synthesis of Prussian Blue nanoobjects of 12-50 nm stabilized within * To whom correspondence should be addressed. E-mail: Joulia.Larionova@ univ-montp2.fr (J.L.);
[email protected] (Y.G.). Fax: (33) 4 67 14 38 52. † Université Montpellier II. ‡ Russian Academy of Science.
(1) Schmid, G. Nanoparticles: From Theory to Applications; Wiley-VCH: Weinheim, 2004. (2) (a) Hyeon, T. Chem Commun. 2003, 927. (b) Klabunde, K. J. In Nanoscale Materials in Chemistry; Klabunde, K. J., Ed.; Wiley Intersciences: New York, 2001. (c) Diehl, M. R.; Yu, J.-Y.; Heath, J. R.; Doyle, G. A.; Sun, S.; Murray, C. B J. Phys. Chem. B 2001, 105, 7913. (d) Leslie-Pelescky, D. L.; Rieke, R. D. Chem. Mater. 1996, 8, 1770. (3) Feldheim, D. L.; Foss, C. A., Jr. Metal Nanoparticles. Synthesis, Characterization, and Applications; Marcel Dekker: New York, 2002. (4) Cushing, B. L.; Kolesnichenko, V. L.; O’Connor, C. J. Chem. ReV. 2004, 104, 3893.
micelles was reported by Mann and co-workers.5 Hereafter, the number of articles devoted to the investigation of coordination nanopolymers is in constant expansion. Indeed, the synthesis of cyano-bridged metallic nanoparticles of different size (
