Phase transition of chemically synthesized FePt nanoparticles under high pressure
We present the results of a study related to phase
transformation of chemically synthesized FePt nanoparticles under high
pressure from face-centered cubic into face-centered tetragonal structure.
As-synthesized nanoparticles are around 4.5 nm and show superparamagnetic
behavior at 300 K. After annealing under 60 bar pressure of hydrogen at 400
∘∘^{\circ}C for 2 h, nanoparticles exhibit strong ferromagnetic behavior
with 5391 Oe coercivity. Results show that high-pressure annealing lowers
the decomposition temperature of the surfactants surrounding nanoparticles
and partially hinders agglomeration arising from heat treatment. The
promising ferromagnetic properties of the FePt nanoparticles after annealing
under high pressure make them suitable for ultrahigh-density memory devices.
___
- Sun, S. H.; Murray, C. B.; Weller, D.; Folks, L.; Moser, A.
Science
2000
,
287
, 1989-1992.
- Weller, D.; Moser, A.; Folks, L.; Best, M. E.; Lee, W.; Toney, M. F.; Schwickert, M.; Thiele, J. U.; Doerner, M. F.
IEEE T. Magn.
2000
,
36
, 10-15.
- Rong, C. B.; Poudyal, N.; Chaubey, G. S.; Nandwana, V.; Skomski, R.; Wu, Y. Q.; Kramer, M. J.; Liu, J. P.
J.
Appl. Phys.
2007
,
102
, 043913.
- Kang, S.; Harrel, J. W.; Nikles, D. E.
Nano Lett.
2002
,
2
, 1033-1036.
- Zeng, H.; Li, J.; Liu, J. P.; Wang, Z. L.; Sun, S. H.
Nature
2002
,
420
, 395-398.
- Shevchenko, E. V.; Talapin, D. V.; Schnablegger, H.; Kornowski, A.; Festin, O.; Svedlindh, P.; Haase, M.; Weller,
H.
J. Am. Chem. Soc.
2003
,
125
, 9090-9101.
- Chen, M.; Liu, J. P.; Sun, S.
J. Am. Chem. Soc.
2004
,
126
, 8394-8395.
- Liu, C.; Wu, X.; Klemmer, T.; Shukula, N.; Yang, X.; Weller, D.; Roy, A. G.; Tanase, M.; Laughlin, D.
J. Phys.
Chem. B
2004
,
108
, 6121-6123.
- Rong, C. B.; Nandwana, V.; Poudyal, N.; Li, Y.; Liu, J. P.; Ding, Y.; Wang, Z. L.
J. Phys. D
2007
,
40
, 712-716.
- Nguyen, H. L.; Howard, L. E. M.; Stinton, G. W.; Giblin, S. R.; Tanner, B. K.; Terry, I.; Hughes, A. K.; Ross, I.
M.; Serres, A; Evans, J. S. O.
Chem. Mater.
2006
,
18
, 6414-6424.
- Sun, S.; Fullerton, E. E.; Weller, D.; Murray, C. B.
IEEE T. Magn
.
2001
,
37
, 1239-1243.
- Harrell, J. W.; Wang, S.; Nikles, D. E.; Chen, M.
Appl. Phys. Lett.
2001
,
79
, 4393-4395.
- Sun, S
. Adv. Mater.
2006
,
18
, 393-403.
- Dai, Z. R.; Sun, S.; Wang, Z. L.
Nano Letters
2001
,
1
, 443-447.
- Lai, C. H.; Wu, Y. C.; Chiang, C. C.
J. Appl. Phys.
2005
,
97
, 10H305.
- Seehra, M. S.; Singh, V.; Dutta, P.; Neeleshwar, S.; Chen, Y. Y.; Chen, C. L.; Chou, S. W.; Chen, C. C
. J. Phys.
D
2010,
43
, 145002.
- Lyubina, J.; Opahle, I.; Richter, M.; Gutfleisch,; Müller, K. H.; Schultz, L.; Isnard, O.
Appl. Phys. Lett.
2006
,
89
,
032506.
- Karcı, Ö.; Dede M.; Oral, A.
Rev. Sci. Inst.
2014
,
85
, 103705.
- Şimşek, T.; Özcan, Ş.
J. Magn. Magn. Mater
.
2014
,
351
, 47-51.