Standard molar Gibbs free energy of formation of Na2ZrO3(s)

Revision of the data on the standard Gibbs free energy of formation of sodium zirconate

“…The results of these measurements though fairly coinciding deviate from the findings of the rest of the approaches, i.e. calorimetry [1], manometry [3] and estimation [5,6], by up to 35 kJ/mol. From the data it can be calculated that the sodium chemical potential established by the heterogeneous phase system Na 2 ZrO 3 /ZrO 2 (NZO)/O 2 is expected to be about as low as that adjusted by the system Na 2 CO 3 /CO 2 , O 2 .…”

“…The knowledge about the thermodynamic stability of Na 2 ZrO 3 is based on four experimental investigations [1][2][3][4] and two numerical estimations [5,6]. There is a considerable scattering in the data reaching over about 46 kJ/mol which corresponds to a value of about 240 mV in terms of the voltage of a potentiometric galvanic cell.…”

Indication of bivariance in the phase system sodium zirconate/zirconia

“…It is discernible that the sodium oxide activity steadily changes upon changing the surrounding conditions. There is no abscissa region within which a Na 2 O remains constant as it ought to be expected from equation (9) for a Na 2 ZrO 3 ¼ 1 and a ZrO 2 ¼ 1. The absence of any plateau in the lg a Na 2 O vs: lg a Na curves indicates that under the measuring conditions no univariant equilibrium exists between Na 2 ZrO 3 and ZrO 2 .…”

Review—Evolution of the Development of In-Sodium Oxygen Sensor and Its Present Status

“…Chemical compatibility with liquid sodium.-Chemical incompatibility of stabilized zirconia electrolytes in sodium at 589 K (316 • C) with a maximum oxygen concentration of ∼50 ppm was reported by Minushkin and Kolodney. 12 Gibbs energy of formation of the reaction product namely sodium zirconate (Na 2 ZrO 3 ) was reported by Iyer et al and Maier et al 14,15 Using this data and the following equilibrium, threshold oxygen concentration in sodium above which this attack would occur can be calculated:…”