New FCC Mg–Zr and Mg–Zr–ti deuterides obtained by reactive milling

• Synthesis and characterization of Mg0.40Zr0.60D1.78 and Mg0.40Zr0.26Ti0.34D1.98.
• New deuterides obtained by milling under H2 gas pressure in the order of a few MPa.
• Phases desorb deuterium at temperature lower than corresponding binary deuterides.
• Mg0.40Zr0.26Ti0.34D1.98 stores hydrogen reversibly at 673 K and 10 MPa of D2.

Results for binary Mg–Zr and ternary Mg–Zr–Ti mixtures ball milled at room temperature under reactive deuterium atmosphere (5.6–6.7 MPa) are reported. X-ray and neutron powder diffraction combined with Rietveld refinements show that two new cubic phases were formed during milling. Mg0.40Zr0.60D1.78 and Mg0.40Zr0.26Ti0.34D1.98 crystallize with disordered face centered cubic metal atom arrangements. Results of differential scanning calorimetry and termogravimetric measurements demonstrate that both deuterides desorb deuterium at lower temperatures than MgD2, ZrD2 or TiD2; 528 and 575 K in the Mg–Zr–D and Mg–Zr–Ti–D system, respectively. Interestingly, Mg0.40Zr0.26Ti0.34D1.98 stores deuterium reversibly at 673 K and 10 MPa of D2.

High resolution SR-PXD patterns obtained for Mg0.40Zr0.60D1.78 and first time reported Mg0.40Zr0.26Ti0.34D1.98.Figure optionsDownload as PowerPoint slide