Vol.:(0123456789) 1 3
Journal of Materials Science: Materials in Electronics
https://doi.org/10.1007/s10854-020-03325-7
Room temperature ferromagnetism in Gd-doped In
2
O
3
nanoparticles
obtained by auto-combustion method
G. Hosamani
1
· B. N. Jagadale
1
· J. Manjanna
2
· S. M. Shivaprasad
3
· D. K. Shukla
4
· J. S. Bhat
5
Received: 16 February 2020 / Accepted: 26 March 2020
© Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract
For spintronic devices, the room temperature ferromagnetism in dilute semiconductors is essential. We report here the suc-
cessful preparation of (In
1−x
Gd
x
)
2
O
3
[x = 0, 0.05, 0.10] by auto-combustion method. The powder XRD and SAED data
confrmed the formation of single-phase cubic bixbyite In
2
O
3
. The particles are in the range of 18–22 nm size. Raman spectra
showed doping of Gd3+ ions in the In
2
O
3
lattice. The 3+ valence state of In and Gd was confrmed from XPS and XAS
techniques. The magnetic hysteresis loop and EPR spectra showed the weak ferromagnetism in (In
0.90
Gdn
0.10
)
2
O
3
, while the
pure In
2
O
3
is diamagnetic and (In
0.95
Gdn
0.05
)
2
O
3
is paramagnetic. To our knowledge, it is the frst study to report the RTFM
in Gd-doped In2O3 nanoparticles.
1 Introduction
Diluted magnetic semiconductors (DMS) have been studied
[1–5] due to their potential application in spintronic devices.
In these materials, a small magnetization is induced by dop-
ing magnetic ions [6, 7]. Doping of transition metal (TM)
ions in conventional semiconductors lead to DMS with
improved optical and magnetic properties. For instance,
SnO
2
, TiO
2
and ZnO exhibited ferromagnetism at room tem-
perature (RT) and above, when doped with small amount
of TM [8–12]. It could be possible to control the spin of
an electron by magnetic, electrical and optical signals [13].
Therefore, they can be used in storing, processing and trans-
mitting information by spin-dependent currents and spin-
based devices. Diferent models such as carrier-mediated
exchange mechanism and the oxygen vacancy-mediated
mechanism are proposed for ferromagnetism in DMS [12,
14].
In
2
O
3
having cubic bixbyite crystal structure is an n-type
transparent semiconductor with wide bandgap (3.5–3.8 eV)
which has potential applications in electronic devices. The-
oretically, TM-doped In
2
O
3
are predicted to be a suitable
material for room temperature DMS [9, 15]. There are many
reports on the room temperature ferromagnetic materials:
Fe-doped In
2
O
3
[16], Co-doped In
2
O
3
[17], Ni-doped In
2
O
3
[18] and Cr, Ti, V-doped In
2
O
3
[19]. However, studies on
rare-earth (RE)-doped semiconductors having RTFM are
limited: for instance, sintered Sm-doped ZnO [20] and Gd-
doped ZnO [21, 22] are reported recently. RE metal ions
such as Gd
3+
and Nd
3+
doping are expected to ofer fer-
romagnetic interaction in the lattice [12, 23]. The enhanced
ferromagnetic moment in Gd-doped lattice is due to the cou-
pling between Gd
3+
ions [3, 24]. When low concentration
of Gd ions is doped in the parent (In
2
O
3
) lattice, possibil-
ity of anti-ferromagnetic ordering is minimized. Thus, it is
important to investigate on the origin of the ferromagnetism
in Gd-doped In
2
O
3
nanocrystals. The ionic radius of Gd
3+
(0.938 Å) is higher than In
3+
(0.80 Å) and hence we have
doped only up to 10 metal at% of Gd
3+
in In
2
O
3
lattice.
Electronic supplementary material The online version of this
article (https://doi.org/10.1007/s10854-020-03325-7) contains
supplementary material, which is available to authorized users.
* J. Manjanna
jmanjanna@redifmail.com
B. N. Jagadale
basujagadale@gmail.com
1
Department of Electronics, Kuvempu University,
Shankaraghatta 577451, India
2
Department of Chemistry, Rani Channamma University,
Belagavi 591156, India
3
International Centre for Materials Science, JNCASR,
Bangalore 560064, India
4
UGC-DAE Consortium for Scientifc Research,
Indore 452001, India
5
Indian Institute of Information Technology,
Ichchanath, Surat 395007, India