Study of the isobaric and isostoichiometric kinetic parameters of oxygen exchange reaction of SrFe0.98Mo0.02O3- MIEC perovskite

Oxygen Exchange in MIEC Perovskite Oxide La0.6Sr0.4Co0.2Fe0.8O3−δ: Kinetic and Equilibrium Parameters and Their Interrelation

“…It is shown in Figure 19 that the entropy factor makes a greater contribution to the change in the Gibbs activation energy (activation barrier) with a relatively small change in the enthalpy. This result is in a good agreement with the literature data, 45,57 in which the change in the Gibbs energy (μO 2 oxide (δ)) in ferrites is almost completely determined by the entropy coefficient, which is caused by the Fe 3+ /Fe 4+ disorder in the oxide lattice. At the same time, in the cobaltites considered in detail in the papers, 24,28,29,33 the dependences of the activation enthalpy R 0 on δ are completely determined by the component of the partial molar enthalpy in μO 2 oxide (δ).…”

“…Another feature of the TPD in addition to the one described in the experimental part is the possibility of obtaining equilibrium dependencies in a different direction from the QEOR equilibrium data, in the direction of temperature change. QEOR gives continuous dependencies 2.05 × 10 −4 (this study) 3.54 × 10 −5 (ECR) 45 3.2 × 10 −8 (IIE) 46 2.69 × 10 −3 (ECR) 47 1 × 10 −3 (ECR) 48 D chem (cm 2 s −1 ) 2 × 10 −6 (this study) 1 × 10 −5 (ECR) 45 5.6 × 10 −9 (IIE) 46 6.31 × 10 −5 (ECR) 47 6.3 × 10 −6 (ECR) 48 a ECR, electronic conductivity relaxation; IIE, isothermal isotope exchange. on composition, and TPD complements them with continuous dependencies on temperature.…”

“…When setting up such an experiment, questions naturally arise not only about the optimal selection of sample geometric dimensions but also about the correct choice of the flow rate, the values of the partial pressures of oxygen, and the value of the pressure step. To do this, it is necessary to refer to the main provisions of the model described in. , According to the model, the working area in which cylindrical samples are located inside the quartz tube can be represented as a chain of continuous stirred tank reactors. This approximation allows us to take into account the inhomogeneity of the conditions that occur when gas flows inside such oxide-filled reactors.…”

“…To do this, it is necessary to refer to the main provisions of the model described in. 41,45 According to the model, the working area in which cylindrical samples are located inside the quartz tube can be represented as a chain of continuous stirred tank reactors. This approximation allows us to take into account the inhomogeneity of the conditions that occur when gas flows inside such oxide-filled reactors.…”

Nanotechnologies in ceramic electrochemical cells

“…For electrodes, the electrochemical reaction properties, such as the gas adsorption ability and ionic conduction capacity, are still confined under a relatively low level. Mixed ionic and electronic conducting electrodes (MIECs, mainly referred to oxygen-ion and electronic conductors) are popular candidates for OCCs, 55 while triple protonic-oxygen ion-electronic conducting electrodes are theoretically and experimentally under evaluation for PCCs. 56 The traditional electrodes are commonly composed of micro-scale grains.…”