Synthesis and characterization of novel ferromagnetic PPy-based nanocomposite
Jing Jiang
a,
⁎
, Chaochao Chen
c
, Lun-Hong Ai
a
, Liang-Chao Li
b,
⁎
, Hui Liu
b
a
Laboratory of Applied Chemistry and Pollution Control Technology, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China
b
Department of Chemistry, Zhejiang Normal University, Jinhua 321004, China
c
Department of Property Management, China West Normal University, Nanchong 637002, China
abstractarticle info
Article history:
Received 4 October 2008
Accepted 18 November 2008
Available online 24 November 2008
Keywords:
Nanomaterials
Magnetic materials
Polypyrrole(PPy)
Magnetic property
Polypyrrole(PPy)/Zn
0.5

0.5
Fe
2
O
4
. The results were
shown that the magnetic parameters such as saturation magnetization and coercivity of Zn
0.5
Cu
0.5
Fe
2
O
4
decreased upon PPy coating.
© 2008 Elsevier B.V. All rights reserved.
1. Introduction
Inherently conducting polymers are attractive materials, as they
cover a wide range of functions from insulators to metals and retain
the mechani cal prope rti e s of conventio na l polymer s [1,2].The
considerable electrochemical and physicochemical properties result
in conducting polymers having various practical applications, such as
corrosion protection coatings, electro-catalysts, chemical sensors,
rechargeable batteries, and light-emitting diodes (LEDs) [3–7].
Among the conducting polymer, polypyrrole (PPy) has received a
great deal of attention in recent years due to its easy synthesis, good
environmental stability, and high electrical conductivity [8].
Organic–inorganic nanocomposites with an organized structure
provide a new functional hybrid between organic and inorganic
materials. In recent years, conducting polymer-based composites

Fe
2
O
4
ferrite-
PPy nanocomposite system has not been reported yet. Herein, we
developed the water-in-oil (w/o) microemulsion process and first
prepared the PPy–Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite with ferromagnetic
behavior. This approach provides a simple, general and inexpensive
method for the preparation of PPy–ferrite nanocomposite.
2. Experimental
Zn
0.5
Cu
0.5
Fe
2
O
4
nanoparticles were prepared by a citrate sol–gel
combustion process. The typical procedure was described in our
previous study [14]. The synthesis of PPy/Zn

⁎ Corresponding author. Tel.: +86 817 2568081; fax: +86 817 2582029.
E-mail address: (J. Jiang).
0167-577X/$ – see front matter © 2008 Elsevier B.V. All rights reserved.
doi:10.1016/j.matlet.2008.11.031
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well-stirred reaction mixture. The reaction was carried out at 0 °C
under nitrogen while stirring for 8 h. The nanocomposite was
obtained by filtering and washing the suspension with methanol,
and dried under vacuum at 60 °C for 24 h.
The X-ray diffraction (XRD) patterns of the samples were collected
on a X-ray diffractometer with Cu Kα radiation. Infrared spectra were
recorded on a Brucker Equinox 55 FT-IR spectrometer in the range of
400–40 00 cm
− 1
using K Br pellets. The SEM micrographs were
obtained on a Hitachi S4800 scanning electron microscope. SEM
measurements were mounted on aluminum studs using adhesive
graphite tape and sputter coated with gold before analysis. Magnetic
measurements were carried out at room temperature using a
vibrating sample magnetometer (VSM) with a maximum magnetic
field of 10 kOe.
3. Results and discussions
The structures of the PPy/Zn
0.5
Cu
0.5
Fe
2

formation vibration at 795 cm
− 1
and the C–C out-of-plane ring defor-
mation vibration at 617 cm
− 1
canbeobserved.AsshowninFig. 1b, FTIR
spectra of PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite are almost identical to that
of PPy. Due to the higher mass of the participating atoms, vibrations of
transitional metal–oxy gen bonds appear in the far-infrar ed region,
characteristic peaks of the ferritecannotbeexpectedinthepresent
spectral pattern [17].
Fig. 2 shows the XRD patterns of PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocompo-
site. It can be observed that the broad amorphous diffraction peak
centred at around 2θ = 23° in the XRD curves of PPy/Zn

2
O
4
of the JCPDS file No. 77-0012 (b).
Fig. 3. SEM micrographsof Zn
0.5
Cu
0.5
Fe
2
O
4
(a) and PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite (b).
Fig. 4. Magnetization curves of Zn
0.5
Cu
0.5
Fe
2
O
4
(a) and PPy/Zn

O
4
in the PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite.
Fig. 3a shows the SEM micrograph of the as-burnt Zn
0.5
Cu
0.5
Fe
2
O
4
powders synthesized by a self-propagating combustion method,
indicating a characteristic of porous surface, formed by the escaping
gases during the combustion process [19]. Fig. 3b shows the SEM
micrograph of PPy/Zn
0.5
Cu
0.5
Fe
2
O
4

Cu
0.5
Fe
2
O
4
nanocompos ite is lower t han th at of Zn
0.5
Cu
0.5
Fe
2
O
4
, due to
the diamagnetic PPy contribution to the total magnetization [20].
Magnetic properties observed for materials are a combination
of many anisotropy mechanisms, such a s magnetocrysta lline
anisotropy, surface anisotropy and interparticles interactions. For the
PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite system, PPy coating may decrease
the surface anisotropy of Zn
0.5

which is related to the microstructure, is larger than that of the
sample obtained by w/o microemulsion route (Table 1), indicating that
Zn
0.5
Cu
0.5
Fe
2
O
4
nanoparticles are more homogeneously embedded in
PPy matrix by w/o microemulsion route.
4. Conclusions
In summary, the ferromagnetic PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocompo-
site was successfully synthesized via in-situ polymerization of pyrrole
in the presence of Zn
0.5
Cu
0.5
Fe
2
O

[4] Ficicoglu F, Kadirgan F. J Electroanal Chem 1998;451:95–9.
[5] Kan JQ, Pan XH, Chen C. Biosens Bioelectron 2004;19:1635–40.
[6] Kuwabata S, Masui S, Yoneyama H. Electrochim Acta 1999;44:4593–600.
[7] Wang HL, MacDiarmid AG, Wang YZ, Gebler DD, Epstein AJ. Synth Met 1996;78:33–7.
[8] Skotheim TA, Elsenbaumer R, Reynolds JR. Handbook of Conducting Polymers.
New York: Marcel Dekker; 1998.
[9] Alam J, Riaz U, Ahmad S. J Magn Magn Mater 2007;314:93–9.
[10] Deng J, Peng Y, He C, Long X, Li P, Chan ASC. Polym Int 2003;52:1182–7.
[11] Qiu G, Wang Q, Nie M. Macromol Mater Eng 2006;291:68–74.
[12] Pileni MP. Adv Funct Mater 2001;5:323–36.
[13] Song Q, Zhang ZJ. J Am Chem Soc 2004;126:6164–8.
[14] Jiang J, Ai LH. Appl Phys A 2008;92:341–4.
[15] He C, Yang C, Li Y. Synth Met 2003;139:539–45.
[16] Blinova NV, Stejskal J, Trchová M, Prokeš J, Omastová M. Eur Polym J 2007;43:2331–41 .
[17] Jiang J, Li L, Zhu M. React Funct Polym 2008;68:57–62.
[18] Seo I, Pyo M, Cho G. Langmuir 2002;18:7253–7.
[19] Xue H, Li Z, Wang X, Fu X. Mater Lett 2007;61:347–50.
[20] Xu P, Han X, Wang C, Zhao H, Wang J, Wang X, et al. J Phys Chem B 2008;112:2775–81.
[21] Vestal CR, Zhang ZJ. J Am Chem Soc 2002;124:14312–3.
[22] Vestal CR, Zhang ZJ. Nano Lett 2003;3:1739–43.
Table 1
Magnetic parameters of PPy/Zn
0.5
Cu
0.5
Fe
2
O
4
nanocomposite synthesized by different r oute