Synthetic Metals 161 (2011) 990–995 Contents lists available at ScienceDirect Synthetic Metals journal homepage: www.elsevier.com/locate/synmet Preparation and characterization of PAn/NiO nanocomposite using various surfactants Mahdi Aleahmad a , Hamidreza Ghafouri Taleghani a , Hossein Eisazadeh b,∗ a Faculty of Chemical Engineering, Mazandaran University, Babolsar, Iran b Faculty of Chemical Engineering, Babol Noshirvani University of Technology, P.O. Box 484, Babol, Iran article info Article history: Received 15 January 2011 Received in revised form 27 February 2011 Accepted 5 March 2011 Available online 20 April 2011 Keywords: Nanocomposite Polyaniline Surfactant Morphology Conductivity abstract Conducting nanocomposite of NiO–PAn has been prepared in the aqueous medium using polyvinyl alco- hol and hydroxypropylcellulose as a surfactant. The conductivity of the composites was measured as a function of the NiO concentration in reaction solution. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and electrical resistivity proved that NiO affect the properties of composite. © 2011 Elsevier B.V. All rights reserved. 1. Introduction Conducting polymers, a unique class of materials that exhibit electrical and optical properties of metals or semiconductors, have presented a great prospects for practical applications due to their unparalleled architectural diversity and flexibility, inex- pensiveness, and easiness of synthesis. It was expected that conducting polymers would find their potential applications in multidisciplinary areas such as electrical, electronics, ther- moelectric, electrochemical, electromagnetic, electromechanical, electro-luminescence, electro-rheological, chemical, membrane, and sensors [1–5]. Recently, new development appeared in design and synthesis of superparamagnetic materials. Several organic–magnetic com- posites have been reported exhibiting ferromagnetic behaviors. Gemeay et al. had reported an oxidative polymerization method to prepare PANI/MnO 2 composite [6]. Lin et al. also prepared Fe 3 O 4 /polypyrrole composite [7]. Recently, polyaniline (PAn) has attracted much attention because of its several unique proper- ties. It shows magnetic behavior because of its high spin density [8]. Yoshino et al. have reported that ferromagnetic spin–spin interaction was observed in poly(m-aniline). The copolymer of aniline and 5-amino-2-napthalenesulfonic acid has ferromagnetic properties with a positive Weiss constant of 12 K, and its ferro- ∗ Corresponding author. Fax: +98 1113234201. E-mail address: Eisazadeh@hotmail.com (H. Eisazadeh). magnetic behavior depends on acidic treatment [9]. Preparation of polyaniline with ferromagnetic properties has been mostly stud- ied by Wan’s group through two approaches: (i) blending the polyaniline in N-methyl-2-pyrrolidone (NMP) with iron (II) sul- fate aqueous solution and (ii) precipitating Fe 2+ into maghemite [10]. Magnetic nanocomposites have many possible technological applications. Numerous reviews have been devoted to the appli- cation of magnetic beads in the biomedical field [11–16]. These composite particles can be used for therapeutic or analytical pur- poses. In the first case, magnetic particle carries permit either the guiding and release of a drug in a specific site of the body [13,17] or the extraction of tumour cells from the organism and their curing in vitro [15,16]. In both cases, toxicity and the secondary effects of a strong chemical in vivo treatment are avoided. Magnetic particles were found suitable as solid phases in immunoassays, since after the capture step the target molecules can easily be separated upon applying a magnetic field [14,18]. Organic materials having an electrical and/or magnetic func- tion have been attractive because of their unique properties and application aspects in technology. Among the conducting polymers, polyaniline has been of particular interest because of its various structures, special doping mechanism, excellent environmental stability, and wide applications as electronic materials. Polyani- line (PAn) has a reactive N–H group in a polymer chain flanked on either side by a phenylene ring, imparting a very high chemical flexibility. It undergoes protonation and deprotonation in addi- tion to adsorption through nitrogen, which having alone pair of 0379-6779/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.synthmet.2011.03.005