Abstract: A ceramic composition having a high adsorptive capacity for oxygen at elevated temperature, including at least one of: Bi2−yEryO3−d; Bi2−yYyO3−d; La1−yBayCo1−xNixO3−d; La1−ySryCo1−xNixO3−d; La1−yCayCo1−xNixO3−d; La1−yBayCo1−xFexO3−d; La1−ySryCo1−xFexO3−d; and La1−yCayCo1−xFexO3−d; wherein x is from 0.2 to 0.8, y is from 0 to 1.0 and d=0.1 to 0.9. Such ceramic composition may be made using a modified Pechini synthetic procedure. The resulting ceramic composition is usefully employed as an adsorbent for separation of oxygen from an oxygen-containing feed gas mixture, e.g., in a pressure swing adsorption (PSA) process.

Abstract: A pressure swing adsorption system for processing an oxygen-containing feed gas mixture to extract oxygen therefrom, comprising an adsorbent bed arranged for elevated temperature sorption/desorption operation, wherein the adsorbent bed comprises a ceramic adsorbent having affinity for oxygen when the ceramic adsorbent is at elevated temperature. Suitable ceramic adsorbents include lanthanum calcium cobalt ferrites and other oxygen ionic transport ceramic metal oxide compositions. As applied to the separation of air or other oxygen/nitrogen mixtures, the PSA system is effective to produce oxygen-rich as well as nitrogen-rich product gases.

Abstract: A semiconductor wafer base is disclosed which is suitable for fabrication of devices in silicon carbide, comprising a single crystal substrate which is a transition metal carbide alloy having cubic crystal structure and an unpolytyped, single crystal 3C-silicon carbide overlay epitaxially related to the substrate. Preferably, the substrate is an alloy of two or more of titanium carbide, tantalum carbide, vanadium carbide, and niobium carbide, with lattice parameter differing from 3C-silicon carbide by less than about 1%. Use of the transition metal carbide alloys enables the preparation of large, single crystal substrates free from cracks, dislocations, or other defects, suitable for epitaxial deposition of 3C-silicon carbide. The 3C-silicon carbide epitaxial overlay may be deposited by any suitable technique, including chemical vapor deposition and reactive evaporation, and may be doped with n- or p-type dopants.

Abstract: A semiconductor wafer base is disclosed which is suitable for fabrication of devices in silicon carbide, comprising a single crystal substrate which is a transition metal carbide alloy having cubic crystal structure and an unpolytyped, single crystal 3C-silicon carbide overlay epitaxially related to the substrate. Preferably, the substrate is an alloy of two or more of titanium carbide, tantalum carbide, vanadium carbide, and niobium carbide, with alttice parameter differing from 3C-silicon carbide by less than about 1%. Use of the transition metal carbide alloys enables the preparation of large, single crystal substrates free from cracks, dislocations, or other defects, suitable for epitaxial deposition of 3C-silicon carbide. The 3C-silicon carbide epitaxial overlay may be deposited by any suitable technique, including chemical vapor deposition and reactive evaporation, and may be doped with n- or p-type dopants.