Prima-Garcia et al. Nanoscale Research Letters 2012, 7:232 http://www.nanoscalereslett.com/content/7/1/232 N A N O E X P R E S S Open Access Tailoring magnetic properties of electrodeposited thin films of the molecule-based magnet Cr (CN) 11.5H O 5.5 12 2 Helena Prima-Garcia*, Eugenio Coronado, Juan P Prieto-Ruiz and Francisco M Romero Abstract This paper reports on molecular-based magnetic thin films of Prussian blue analogues (PBA) with high critical temperatures composed of mixed-valence chromium cyanides. The thin films of PBA were synthesized by means of electrodeposition technique. Morphology and magnetic study are presented in a function of electrochemical deposition conditions. We present the electrochemical methods as a promising and effective tool for preparing molecular-based magnetic thin films of Prussian blue analogue. Keywords: Magnetic materials, Thin films, Molecule-based magnet, Prussian blue, MOKE Background The family of Prussian blue analogues (PBA) of general formula CcAa[B(CN)6]b nH2O (C, alkali cation; A and B, transition metal ions) are molecule-based materials with interesting magnetic properties. Electrochemical methods have been extensively used to fabricate high-quality films of molecule-based materials with interest in molecular spintronics such as PBAs [1-3]. Electrodeposition is considered as a real alternative to physical deposition techniques, such as evaporation, sput- tering, and molecular beam epitaxy, in order to provide a simple and cost-effective technology for the preparation of high-quality films and multilayers [4,5]. Electrochemical methods are intrinsically fast and compatible with pattern- ing and large-scale production [6] with the possibility of working in wet non-vacuum conditions. In this way, electrodeposition is presented as one of the simplest and cheapest processes available for the fabrication of thin films [7] being of great interest in possible industrial applications. In this work, we report on the fabrication and characterization of Prussian blue analogue thin films obtained by electrodeposition, showing this technique as a promising and effective tool for preparing high-quality thin * Correspondence: helena.prima@uv.es Instituto de Ciencia Molecular, Universidad de Valencia, Catedrático José Beltrán 2, Paterna (Valencia), 46980, Spain films of this molecule-based magnet with great perspectives in the field of molecular spintronics. Methods Preparation of the films All reagents were purchased from Sigma-Aldrich (St. Louis, MO, USA) and used without further purification. The electrochemical synthesis of the PBA CrI3I.5[CrIII(CN)6] [CrII(CN)6] 11.5H2O has been described in previous works [8]. An aqueous solution containing K3[Cr(CN)6] (5 mmol) and CrCl3 (7.5 mmol) was reduced at a fixed potential (E = −0.88 V vs Ag/AgCl reference electrode) on a substrate of Mylar or glass (dimension 5 × 10 mm) coated with an evaporated Au layer of 100-nm thickness. This substrate was used as the working electrode. A Metrohm Autolab potentiostat (Kanaalweg, Utrecht, The Netherlands) in coulometry mode was employed for depositing the transparent films with a Pt wire as a coun- ter electrode. After preparation, films were rinsed with deionized water and dried at room temperature. Films of different thicknesses were obtained by varying the time of deposition. The thicknesses were determined using an Ambios Technology XP-1 profilometer (Milpitas, CA, USA) placed on a vibration isolation table. AFM -study A Nanoscope Multimode (Veeco Instruments Inc., Plainview, NY, USA) atomic force microscopy in tapping © 2012 Prima-Garcia et al.; licensee Springer. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.