Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Observation of Phase Transitions in Hydrogenated Y Films Via IR Emissivity Imaging



Jason Hattrick-Simpers, Ke Wang, Raymond Cao, Chun Chiu, Edwin J. Heilweil, Robert G. Downing, Leonid A. Bendersky


Direct observation of a sequence of phase transitions during hydrogenation of Y thin films has been realized through the use of in-situ isothermal IR emissivity measurements. The formation of different phases, α-Y(H), YH2 and YH3, has been identified based on observation of the changes in the slope of the IR emissivity vs. time curve during the hydrogen loading experiments. The presence of the appropriate phases was confirmed by ex-situ x-ray diffraction and Prompt Gamma Activation Analysis (PGAA). Transmission electron microscopy (TEM) demonstrated single crystal orientation relationships between the Al2O3 substrate, Ti buffer layer, the as-deposited Y film, as well as its hydrides. These results clearly demonstrate the power of IR emissivity imaging to monitor, in real time, the formation of hydride phases of both metallic and insulating character near the surface of a thin-film sample.
Journal of Alloys and Compounds
490 (2010)


hydrogen storage, Yttrium tri-hydride, Yttrium di-hydride, IR imaging


Hattrick-Simpers, J. , Wang, K. , Cao, R. , Chiu, C. , Heilweil, E. , Downing, R. and Bendersky, L. (2009), Observation of Phase Transitions in Hydrogenated Y Films Via IR Emissivity Imaging, Journal of Alloys and Compounds, [online], (Accessed April 18, 2024)
Created October 20, 2009, Updated November 10, 2018