Here, we report on a giant dielectric relaxation in (1 − x)Bi0.5K0.5TiO3xBiFeO3 ceramics below ∼300 °C, which becomes more pronounced with increasing BiFeO3 content. The relaxation was shown to be of Maxwell-Wagner type and associated with charge depletion at the electroded interfaces. It was also shown that the relaxation could be controlled or, eventually, removed by heat treatment in controlled partial pressure of oxygen. This was rationalized by the relationship between the electrical conductivity and variation in the oxidation state of Fe, which is strongly coupled to the partial pressure of oxygen. The results are discussed with emphasis on oxygen diffusion and point defect equilibria involving oxygen vacancies and iron in divalent and tetravalent state. Finally, the barrier-free dielectric properties of the (1 − x)Bi0.5K0.5TiO3xBiFeO3 ceramics are reported.

1.
H.
Matsuo
,
Y.
Noguchi
,
M.
Miyayama
,
M.
Suzuki
,
A.
Watanabe
,
S.
Sasabe
,
T.
Ozaki
,
S.
Mori
,
S.
Torii
, and
T.
Kamiyama
,
J. Appl. Phys.
108
,
104103
(
2010
).
2.
J. M.
Kim
,
Y. S.
Sung
,
J. H.
Cho
,
T. K.
Song
,
M. H.
Kim
,
H. H.
Chong
,
T. G.
Park
,
D.
Do
, and
S. S.
Kim
,
Ferroelectrics
404
,
88
(
2010
).
3.
T.
Ozaki
,
H.
Matsuo
,
Y.
Noguchi
,
M.
Miyayama
, and
S.
Mori
,
Jpn. J. Appl. Phys.
49
,
09MC05
(
2010
).
4.
A. V.
Pushkarev
,
N. M.
Olekhnovich
, and
Y. V.
Radyush
,
Inorg. Mater.
47
(
7
),
774
(
2011
).
5.
A. V.
Pushkarev
,
N. M.
Olekhnovich
, and
Y. V.
Radyush
,
Phys. Solid State
53
(
3
),
522
(
2011
).
6.
M. I.
Morozov
,
M.-A.
Einarsrud
,
T.
Grande
, and
D.
Damjanovic
,
Ferroelectrics
439
,
88
(
2012
).
7.
M. I.
Morozov
,
M.-A.
Einarsrud
, and
T.
Grande
,
Appl. Phys. Lett.
101
,
252904
(
2012
).
8.
J.
Bennett
,
A. J.
Bell
,
T. J.
Stevenson
,
R. I.
Smith
,
I.
Sterianou
,
I. M.
Reaney
, and
T. P.
Comyn
,
Mater. Lett.
94
,
172
(
2013
)
9.
M. I.
Morozov
,
T.
Grande
, and
M.-A.
Einarsrud
, “
Control of conductivity and piezoelectric performance in bulk Bi0.5K0.5TiO3–BiFeO3 ceramics
,” (unpublished).
10.
G.
Catalan
and
J. F.
Scott
,
Adv. Mater.
21
,
2463
(
2009
).
11.
P.
Ravindran
,
R.
Vidya
,
A.
Kjekshus
, and
H.
Fjellvåg
,
Phys. Rev. B
74
,
224412
(
2006
).
12.
S. A.
Fedulov
,
Dokl. Akad. Nauk SSSR
139
,
1345
(
1961
);
S. A.
Fedulov
,
[Engl. Transl.: Sov. Phys. Dokl.
6
,
729
(
1962
)].
13.
S. M.
Selbach
,
M.-A.
Einarsrud
, and
T.
Grande
,
Chem. Mater.
21
,
169
(
2009
).
14.
T.
Rojac
,
M.
Kosec
,
B.
Budic
,
N.
Setter
, and
D.
Damjanovic
,
J. Appl. Phys.
108
,
074107
(
2010
).
15.
T.
Rojac
,
M.
Kosec
, and
D.
Damjanovic
,
J. Am. Ceram. Soc.
94
(
12
),
4108
(
2011
).
16.
R.
Mazumder
,
S.
Ghosh
,
P.
Mondal
,
D.
Bhattacharya
,
S.
Dasgupta
,
N.
Das
,
A.
Sen
,
A. K.
Tyagi
,
M.
Sivakumar
,
T.
Takami
, and
H.
Ikuta
,
J. Appl. Phys.
100
,
033908
(
2006
).
17.
S.
Kamba
,
D.
Nuzhnyy
,
M.
Savinov
,
J.
Šebek
,
J.
Petzelt
,
J.
Prokleška
,
R.
Haumont
, and
J.
Kreisel
,
Phys. Rev. B
75
,
024403
(
2007
).
18.
P.
Tirupathi
and
A.
Chandra
,
J. Alloys Compd.
564
,
151
(
2013
).
19.
X.
Marti
,
P.
Ferrer
,
J.
Herrero-Albillos
,
J.
Narvaez
,
V.
Holy
,
N.
Barrett
,
M.
Alexe
, and
G.
Catalan
,
Phys. Rev. Lett.
106
,
236101
(
2011
).
20.
Z.
Zhang
,
P.
Wu
,
L.
Chen
, and
J.
Wang
,
Appl. Phys. Lett.
96
,
232906
(
2010
).
21.
T. R.
Paudel
,
S. S.
Jaswal
, and
E. Y.
Tsymbal
,
Phys. Rev. B
85
,
104409
(
2012
).
22.
N.
Maso
and
A. R.
West
,
Chem. Matter.
24
,
2127
(
2012
).
23.
A. R.
Makhdoom
,
M. J.
Akhtar
,
R. T. A.
Khan
,
M. A.
Rafiq
,
M. M.
Hasan
,
F.
Sher
, and
A. N.
Fitch
,
Mater. Chem. Phys.
143
,
256
(
2013
).
24.
P.
Lunkenheimer
,
V.
Bobnar
,
A. V.
Pronin
,
A. I.
Ritus
,
A. A.
Volkov
, and
A.
Loidl
,
Phys. Rev. B
66
,
052105
(
2002
).
25.
P.
Lunkenheimer
,
S.
Krohus
,
S.
Riegg
,
S. G.
Ebbinghaus
,
A.
Reller
, and
A.
Loidl
,
Eur. Phys. J. Spec. Top.
180
,
61
(
2009
).
26.
A. A.
Bokov
and
Z.-G.
Ye
,
J. Adv. Dielectr.
2
,
1241010
(
2012
).
27.
S. M.
Sze
,
Semiconductor Devices: Physics and Technology
, 2nd ed. (
Wiley
,
New York
,
2001
).
28.
L.
Pintilie
and
M.
Alexe
,
J. Appl. Phys.
98
,
124103
(
2005
).
29.
L.
Pintilie
,
I.
Boerasu
,
M. J. M.
Gomes
,
T.
Zhao
,
R.
Ramesh
, and
M.
Alexe
,
J. Appl. Phys.
98
,
124104
(
2005
).
30.
J.
Seidel
,
P.
Maksymovych
,
Y.
Batra
,
A.
Katan
,
S.-Y.
Yang
,
Q.
He
,
A. P.
Baddorf
,
S. V.
Kalinin
,
C.-H.
Yang
,
J.-C.
Yang
,
Y.-H.
Chu
,
E. K. H.
Salje
,
H.
Wormeester
,
M.
Salmeron
, and
R.
Ramesh
,
Phys. Rev. Lett.
105
,
197603
(
2010
).
31.
T.
Ishigaki
,
S.
Yamauchi
,
K.
Kishio
,
J.
Mizusaki
, and
K.
Fueki
,
J. Solid State Chem.
73
,
179
(
1988
).
32.
D. C.
Arnold
,
K. S.
Knight
,
F. D.
Morrison
, and
P.
Lightfoot
,
Phys. Rev. Lett.
102
,
027602
(
2009
).
33.
R.
Schmidt
,
J.
Ventura
,
E.
Langenberg
,
N. M.
Nemes
,
C.
Munuera
,
M.
Varela
,
M.
Garcia-Hernandes
,
C.
Leon
, and
J.
Santamaria
,
Phys. Rev. B
86
,
035113
(
2012
).
34.
R.
Schmidt
,
W.
Eerenstein
, and
P. A.
Midgley
,
Phys. Rev. B
79
,
214107
(
2009
).
35.
G.
Catalan
,
Appl. Phys. Lett.
88
,
102902
(
2006
).
36.
G.
Catalan
and
J. F.
Scott
,
Nature
448
,
E4
(
2007
).
37.
J.
Hemberger
,
P.
Lunkenheimer
,
R.
Ficht
,
H.-A.
Krug fon Nidda
,
V.
Tsurkan
, and
A.
Loidl
,
Nature
434
,
364
(
2005
).
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