Phase Stability Control of Interstitial Oxide Ion Conductivity in the La1+xSr1-xGa3O7+x/2 Melilite Family

DOI: 10.1021/cm903132w

Authors: Matthew Rosseinsky (University of Liverpool) , Xiaojun Kuang (University of Liverpool) , Zengqiang Deng (University of Liverpool) , Hongjun Niu (University of Liverpool) , John Claridge (University of Liverpool)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Chemistry Of Materials , VOL 22 (8)

State: Published (Approved)
Published: March 2010

Abstract: The two-dimensional polyhedral anion network melilites La1+xSr1?xGa3O7+0.5x exhibit interstitial oxide ion conductivity. The solid solution is shown to extend to x = 0.64, and the variation of the conductivity with x is investigated. At high temperatures, all of these compounds adopt the typical tetragonal melilite structure. When x > 0.6, cooling below 600 °C results in a reversible phase transition to an orthorhombic structure which reduces the ionic conductivity. Quenching experiments have shown the tetragonal structure has a higher conductivity compared to the orthorhombic structure of the same composition. Short-range order effects associated with this transition exercise an important influence on the composition- and temperature-dependence of the conductivity.

Subject Areas: Materials


Instruments: I11-High Resolution Powder Diffraction

Added On: 01/04/2010 12:24

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