Transport numbers of H+ and O2- in the electrochemical system (H2 + H2O),Me/BaCe0.9Nd0.1O3-α/Me,(H2 + H2O)

Electrical conductivity of BaCe0.9Nd0.1O3−α in H2+H2O+Ar gas mixture

“…This is in agreement with published data [14], in which it was shown that the mass of water dissolved in BaCe0.gNdo:O3~ decreased with a rise in temperature. On the other hand, the fact that the electroconductivity of BaCe0.gNdojO3~ does not depend on the oxygen partial pressure confirms our earlier conclusion [9] about a small transport number of electrons (L < 0.02) at Po.~ = 10-21 -10 -26 arm at temperature range between 873 to 1123 K. The results obtained were processed using a model, which assumes that a proton is transferred from one occupied oxygen site OH o to another site Oo x, while an oxygen ion Oo x is transferred by a vacancy mechanism. If we assume that the number of sites Og is much larger than the …”

“…Temperature dependencies of the transport numbers of protons and oxygen in BaCe09Ndo.,O3_ a may be calculated using the obtained values of the Kl, I.t H and Po at different temperatures. Figure 5 (a, b) presents experimental depen- dencies of the transport numbers of protons and oxygen ions adopted from [9] and our calculated curves. The researchers [9] determined the transport numbers in a wet H2+Ar gas mixture at room temperature, i.e.…”

“…The activity of oxygen in the "~" -5.0-gas was determined using an oxygen sensor based on a -5.2-stabilized zirconium dioxide. The method for calculating the -5.4 composition of the gas mixture (PH2, Pmo) in binary -5.5 H2+H20 and ternary H2+H20+Ar mixtures was described in detail elsewhere [9]. The feed rate of the H2+H20 mixture and argon was 1.5 to 2.0 f/h and 2.0 to 16.0 f/h, respectively.…”

“…There are few papers dedicated to the behavior of the BaCe~_xRxO3_~ electrolyte in reducing gas atmospheres with a large hydrogen concentration [9][10][11]. We determined the transport numbers in the (HztH20+Ar),Me/BaCe09Ndo LO3-a system [9] and showed that at a temperature below 1123 K the electroconductivity was almost purely ionic (protonic and oxygen-ionic), since the fraction of the ion transport was over 0.98.…”

“…We determined the transport numbers in the (HztH20+Ar),Me/BaCe09Ndo LO3-a system [9] and showed that at a temperature below 1123 K the electroconductivity was almost purely ionic (protonic and oxygen-ionic), since the fraction of the ion transport was over 0.98. The experiments [10] performed at a temperature above 1073 K in a reducing gas atmosphere revealed an increase in the electroconductivity of BaCe0.gGdoAO2.95, which was related to appearance of the electron conductivity.…”