The effect of chelating/combustion agent on catalytic activity and magnetic properties of Dy doped NieZn ferrite P. Samoila a , T. Slatineanu a , P. Postolache b , A.R. Iordan a , M.N. Palamaru a, * a Faculty of Chemistry, Alexandru Ioan Cuza University of Iasi, 11 Carol I Boulevard 700506, Romania b Faculty of Physics, Alexandru Ioan Cuza University of Iasi, 11 Carol I Boulevard 700506, Romania highlights graphical abstract < NieZn ferrite doped with Dy as catalyst and magnetic material. < Four chelating/combustion agents were used in solegel method. < Citric acid and cellulose allowed spinel monophase formation confirmed by XRD. < Catalytic activity of ferrite samples is affected by synthesis conditions. < Magnetic behavior is not changed significantly as a function of fuel agent. article info Article history: Received 22 December 2011 Received in revised form 13 June 2012 Accepted 26 June 2012 Keywords: Nanostructures Fourier transform infrared spectroscopy X-ray diffraction Electron microscopy Magnetic properties abstract The spinel ferrite Ni 0.8 Zn 0.2 Fe 1.98 Dy 0.02 O 4 was prepared by solegel low temperature autocombustion method using four different chelating/combustion agents: citric acid, tartaric acid, urea and cellulose. Infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer eEmmetteTeller (BET) specific surface area measurement, the catalytic H 2 O 2 decomposition and the magnetic behavior were employed to investigate the influence of the combustion agents on structural characteristics, catalytic activity and magnetic properties. Spinel-type phase in the nano-scale domain was accomplished during solegel synthesis and was confirmed by XRD and IR. The best catalytic activity is belonging to the sample obtained using urea, which shows the smallest grain size (SEM), the highest specific surface area (BET measurements) and DyFeO 3 phase (XRD), while ferrimagnetic behavior prevails for all the samples independently of fuel agent. Ó 2012 Elsevier B.V. All rights reserved. 1. Introduction Spinel ferrites M 1x M 0 x Fe 2y RE y O 4 , where M and M 0 are bivalent metals (e.g. cobalt, manganese, nickel, zinc) and RE is a rare earth metal, are technologically attractive due to their promising magnetic properties. Thereby the ferrospinels find extensive application in microwave devices [1], radar [2], ferro-fluids [3] or catalysis [4]. Furthermore, spinel ferrites are well known catalysts for various processes like the oxidative dehydrogenation of hydrocarbons [5], the decomposition of alcohols [6], the selective oxidation of carbon monoxide [7] and the decomposition of hydrogen peroxide [8]. Thereby, the isomorphic substitutions of the cations in the spinel structure plays a significant role both in magnetic properties and in tuning the catalytic properties of the material. Applications of these mixed oxides depends on the high-quality powder synthesized by various methods like solid-state reaction [9], solegel [10], hydrothermal [11], thermal decomposition [12], vapor deposition [13], arc discharge [14], sonolysis [15] or co- precipitation [16] were reported in the literature. Among these * Corresponding author. Tel.: þ40 232201341; fax: þ40 232201313. E-mail address: palamaru@uaic.ro (M.N. Palamaru). Contents lists available at SciVerse ScienceDirect Materials Chemistry and Physics journal homepage: www.elsevier.com/locate/matchemphys 0254-0584/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.matchemphys.2012.06.059 Materials Chemistry and Physics 136 (2012) 241e246