Location

University of Nevada, Las Vegas

Start Date

3-8-2010 9:00 AM

End Date

3-8-2010 12:00 PM

Description

The potential application of intermetallic compounds (IMC) under high hydrogen pressure in studies of hydrogen sorption properties is defined by two important properties. Intermetallics of Laves phases have a suitable binding energy for hydrogen which allows its absorption or desorption near room temperature and atmospheric pressure. High pressures allow to efficiently interact hydrogen with intermetallics, which were considered nonhydride forming [1,2]. For example, ZrFe2, ZrCo2, and ZrFe2 possess fairly high hydrogen absorption capacity at high pressures [3]. A nonactivated ZrFe2 sample starts to interact with hydrogen only at 80 MPa, while equilibrium absorption and desorption pressures of the activated alloy on a plateau are 69 and 32.5 MPa, respectively. Even though ZrFe2 and related Laves phases are subjected only to moderate hydrogen pressures during absorption and desorption, it is essential to understand the structural phase stability under variable pressure-temperature conditions. The present investigation is aimed to study the pressure induced structural changes in ZrFe2 using synchrotron powder x-ray diffraction. High pressure structural studies were performed up to 50 GPa using a diamond anvil cell in the angle dispersion geometry.

Keywords

High pressure (Science); Hydrogen – Absorption and adsorption; Intermetallic compounds; Zirconium compounds

Disciplines

Biological and Chemical Physics | Physical Sciences and Mathematics | Physics

Language

English

Comments

Poster research sponsored by NSF REU


Share

COinS
 
Aug 3rd, 9:00 AM Aug 3rd, 12:00 PM

High pressure x-ray diffraction studies on ZrFe2: A potential hydrogen absorption medium

University of Nevada, Las Vegas

The potential application of intermetallic compounds (IMC) under high hydrogen pressure in studies of hydrogen sorption properties is defined by two important properties. Intermetallics of Laves phases have a suitable binding energy for hydrogen which allows its absorption or desorption near room temperature and atmospheric pressure. High pressures allow to efficiently interact hydrogen with intermetallics, which were considered nonhydride forming [1,2]. For example, ZrFe2, ZrCo2, and ZrFe2 possess fairly high hydrogen absorption capacity at high pressures [3]. A nonactivated ZrFe2 sample starts to interact with hydrogen only at 80 MPa, while equilibrium absorption and desorption pressures of the activated alloy on a plateau are 69 and 32.5 MPa, respectively. Even though ZrFe2 and related Laves phases are subjected only to moderate hydrogen pressures during absorption and desorption, it is essential to understand the structural phase stability under variable pressure-temperature conditions. The present investigation is aimed to study the pressure induced structural changes in ZrFe2 using synchrotron powder x-ray diffraction. High pressure structural studies were performed up to 50 GPa using a diamond anvil cell in the angle dispersion geometry.