Oxide ion conductive ceramic membrane structures for high-pressure oxygen production

Ceramic membrane conducting by oxide ions, characterized in that it comprises a non-zero finished volume of non-zero total thickness T, comprising:

• a) a dense layer (DL) of a solid electrolyte having, at the electrolysis temperature, a crystal structure conducting by oxide ions, of non-zero thickness t0 and of opposed external surfaces S0 and S′0 that are identical or different;
• b) a layer called the tie layer (TL) that possesses either a crystal structure conducting by oxide ions or a hybrid conducting crystal structure or a mixture of the two aforementioned crystal structures, the said tie layer being pressed against the surface S0 of the dense layer (DL), having a non-zero thickness t1, an external surface S1, a specific surface area s1ω and a roughness R1;
• c) a hybrid conducting porous cathode (PE) and a hybrid conducting porous anode (PE′), of identical or different chemical compositions, pressed one against the surface S1 of (TL) and the other against the surface S′0 of (DL), the said electrodes having respectively, external surfaces S2 and S′2 of non-zero area, that are identical or different, and non-zero thicknesses t2 and t′2, that are identical or different;
• and
• d) a cathode current collector (CC) and an anode current collector (CC′), of identical or different chemical compositions, pressed respectively against the surfaces S2 and S′2 of (PE) and (PE′), the said collectors (CC) and (CC′) having external surfaces S3 and S3′ of non-zero area, that are identical or different, and non-zero thicknesses t3 and t′3, that are identical or different, respectively;
• e) a porous covering layer (CL) formed from a material or a mixture of materials chemically compatible with the materials, or mixtures of materials, of the said electrodes, current collectors, tie layer and solid electrolyte, the sintering temperature of which is very close to the sintering temperatures of the constituent materials, or mixtures of materials, of the said of the said electrodes, current collectors, tie layer and solid electrolyte, the said layer (CL) being pressed against the surface S3 of (CC), and optionally
• f) a porous covering layer (CL′) made of a material or a mixture of materials that are chemically compatible with the materials or mixtures of materials of the said electrodes, current collectors and solid electrolyte, the sintering temperature of which is very close to the sintering temperatures of the constituent materials or mixtures of materials of the said of the said electrodes, current collectors, tie layer and solid electrolyte, the said layer (CL′) being pressed against the surface S3′ of (CC′), the said covering layer having a surface S′4 and a non-zero thickness t′4;
• and characterized in that the thickness T of the volume of the said membrane is equal to the sum of the thicknesses of each of the elements mentioned.