Dilawar, Nita and Varandan, Deepak and Pandey, V. P. and Kumar, Mahesh and Shivaprasad, S. M. and Sharma, P. K. and Bandyopadhyay, A. K. (2006) Structural transition in nanostructured Eu2O3 under high pressures. Journal of Nanoscience and Nanotechnology, 6. pp. 1-9. ISSN 1533-4880

PDF - Published Version Restricted to Registered users only Download (1505Kb) | Request a copy

Abstract

We report here studies on the effect of high pressure on the structural properties of nano-sized Europium sesquioxide (Eu2O3) up to a pressure of about 16.4 GPa. At ambient conditions, the starting sample was found to be predominantly cubic type Eu2O3 or in Eu3+ state with a trace of Eu2+. The presence of Eu2+ state is assumed to be arising due to the non-stoichiometric Eu1-xO phase which is obtained from XPS studies by the deconvolution of the Eu 3d-core levels. The Raman studies at ambient show a strong peak at about 333 cm(-1), which is known to occur due to the F-g mode of cubic Eu2O3 and in a similar way, the XRD data shows major peaks corresponding to the cubic phase of Eu2O3. A Mao-Bell type diamond anvil cell (DAC) was used to generate high pressures for XRD and Raman spectroscopy studies. It was observed that the material undergoes a structural change from cubic to monoclinic structure with an on set transition pressure at around 2 GPa and completes at around 8 GPa. This has been inferred from the fact that above about 2.0 GPa pressure, Raman studies show the emergence of a new peak corresponding to the monoclinic phase which increases in intensity and shifts further with increase in pressure, while the XRD studies show that above about 2.0 GPa, the peaks corresponding to monoclinic phase emerge, which show a slight increase in preferred orientation as the pressure is increased. A detailed discussion has been provided to explain this fact.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s American Scientific Publishers.
Subjects:	Chemistry Materials Science Applied Physics/Condensed Matter Nanoscience/ Nanotechnology
Divisions:	UNSPECIFIED
Depositing User:	Users 27 not found.
Date Deposited:	07 Aug 2018 08:34
Last Modified:	07 Aug 2018 08:34
URI:	http://npl.csircentral.net/id/eprint/2556

Actions (login required)

View Item