Production strategies of asymmetric BaCe0.65Zr0.20Y0.15O3-δ – Ce0.8Gd0.2O2-δ membrane for hydrogen separation. (4th March 2020)

• Record Type: Journal Article
• Authors: Mercadelli, Elisa; Gondolini, Angela; Montaleone, Daniel; Pinasco, Paola; Escolástico, Sonia; Serra, José M.; Sanson, Alessandra
• Is Part Of: International journal of hydrogen energy. Volume 45:Number 12(2020)
• Page Start: 7468
• Page End: 7478
• Publication Date: 2020-03-04
• Subjects: Tape casting -- BCZY-GDC -- Ceramic membranes -- Microstructure; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2019.03.148
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Mixed proton and electron conductor ceramic composites are among the most promising materials for hydrogen separation membrane technology especially if designed in an asymmetrical configuration (thin membrane supported onto a thicker porous substrate). However a precise processing optimization is needed to effectively obtain planar and crack free asymmetrical membranes with suitable microstructure and composition without affecting their hydrogen separation efficiency. This work highlights for the first time the most critical issues linked to the tape casting process used to obtain BaCe0.65 Zr0.20 Y0.15 O3-δ – Ce0.8 Gd0.2 O2-δ (BCZY-GDC) asymmetrical membranes for H2 separation. The critical role of the co-firing process, sintering aid and atmosphere was critically investigated. The optimization of the production strategy allowed to obtain asymmetric membranes constituted by a dense 20 μm-thick ceramic-ceramic composite layer supported by a porous (36%) 750 μm-thick BCZY-GDC substrate. The asymmetric membranes here reported showed H2 fluxes (0.47 mL min −1 cm −2 at 750 °C) among the highest obtained for an all-ceramic membrane. Highlights: The formulation of green support is crucial for the asymmetric membranes production. Increasing ZnO content from 0.7 to 1 wt % enhances the active layer densification. Higher amounts of ZnO as sintering aid are useless. The fluorite-perovskite double phase is preserved controlling the sintering atmosphere. H2 fluxes among the highest for an all-ceramic membrane were recorded.