The continuous production of carbon monoxide (CO) and hydrogen (H 2 ) by dry reforming of methane (CH 4 ) is demonstrated isothermally using a ceramic redox membrane in absence of additional catalysts. The reactor technology realizes the continuous splitting of CO 2 to CO on the inner side of a tubular membrane and the partial oxidation of CH 4 with the lattice oxygen to form syngas on the outer side. La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3‐ δ (LSCF) membranes evaluated at 840–1030 °C yielded up to 1.27 μmol CO s −1 from CO 2 , 3.77 μmol H₂ g −1 s −1 from CH 4 , and CO from CH 4 at approximately the same rate as CO from CO 2 . We compute the free energy of the oxygen vacancy formation for La 0.5 Sr 0.5 B 0.5 B′ 0.5 O 3− δ (B, B′=Mn, Fe, Co, Cu) using electronic structure theory to understand how CO 2 reduction limits dry reforming of methane using LSCF and to show how the CO 2 conversion can be increased by using advanced redox materials such as La 0.5 Sr 0.5 MnO 3− δ and La 0.5 Sr 0.5 Mn 0.5 Co 0.5 O 3− δ .

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The electromechanical coupling in barium titanate ceramics is studied as a function of external bias for thickness resonances in the ultrasonic frequency range. The losses associated with the heating of resonant transducers are shown to be primarily of mechanical rather than dielectric origin. The response near coercive field strengths indicates that the rearrangements of domain patterns take place in at least two separate forms. The relationships of the subsidiary responses, which are observed in ceramics under suitable driving conditions, to the state of internal polarization are discussed. Domain processes of the kind assumed in this study furnish an explanation for the observed constriction of dielectric hysteresis loops.