Preparation and characteristics of various rare earth nitrides

Imamura, H. and Imahashi, T. and Zaimi, M. and Sakata, Y. (2008) Preparation and characteristics of various rare earth nitrides. Journal of Alloys and Compounds, 451. pp. 636-639. ISSN 0925-8388

PDF (Preparation and characteristics of various rare earth nitrides) 1-s2.0-S0925838807009061-main.pdf - Published Version Restricted to Registered users only Download (264kB)

Abstract

Active nanocrystalline nitrides of EuN and YbN with high surface areas were successfully prepared by the thermal decomposition of the rare earth amides (Eu(NH2)2, Yb(NH2)2 and Yb(NH2)3). For the preparation of CeN, PrN and NdN, the direct reaction of the rare earth metals with ammonia was extensively studied to determine optimal conditions. In the reaction of rare earth metals with ammonia, hydrides besides the nitrides were competitively formed. The reaction conditions such as temperatures and ratios of ammonia to rare earth metal were crucial in preferential formation of nitride. The nanocrystalline YbN and EuN readily absorbed large amounts of ammonia even at room temperature upon contact with ammonia (13.3 kPa). The absorbed ammonia existed in at least two forms on/in the nitride; the one was surface-adsorbed ammonia and the other ammonia absorbed in the nitride in a decomposed state. The properties of ammonia absorbed by the nitride were further evaluated by temperature-programmed desorption (TPD), FT-IR and XRD techniques.

Item Type:	Article
Subjects:	T Technology > TP Chemical technology T Technology > TD Environmental technology. Sanitary engineering
Divisions:	Faculty of Manufacturing Engineering > Department of Engineering Materials
Depositing User:	MUHAMMAD ZAIMI ZAINAL ABIDIN
Date Deposited:	07 Feb 2014 08:37
Last Modified:	28 May 2015 04:14
URI:	http://eprints.utem.edu.my/id/eprint/11019
Statistic Details:	View Download Statistic

Actions (login required)

View Item