Correlation of structure, electrical conductivity, and oxygen permeability in strontium cobaltite ceramic membranes. Issue 4 (1st October 2020)

• Record Type: Journal Article
• Authors: Jaiswal, Shivendra Kumar; Kashyap, Vijay Kumar; Kumar, Jitendra
• Is Part Of: Journal of Asian ceramic societies. Volume 8:Issue 4(2020)
• Page Start: 1018
• Page End: 1026
• Publication Date: 2020-10-01
• Subjects: Strontium cobaltite -- perovskite-type oxides -- stability -- oxygen permeation -- conductivity; Ceramics -- East Asia -- Periodicals; Materials science -- Periodicals; 620.1405
• DOI: 10.1080/21870764.2020.1840699
• Languages: English
• ISSNs: 2187-0764

Abstract

ABSTRACT: An attempt has been made to synthesize a highly stable oxygen-deficient strontium cobaltite {SrCoO3-δ (δ = 5/16)} by decomposition of the sol-gel derived oxalate at 1000°C for 10 h in air. The product corresponds to the rhombohedral Sr6 Co5 O15 (93 wt%) and spinel cubic Co3 O4 (7 wt%) phases at room temperature but displays the perovskite-type cubic structure with a ~ 3.953 Å at 900°C. It serves as an excellent material for separation of oxygen from the air and exhibits high oxygen permeability (JO2 ) of 3.0 ml/cm 2 .min at 1000°C for a 1.0 mm thick membrane. The activation energy of the process is found as 22 kJ/mol. Further, both JO2 and conductivity (σ) reveal good correlation with phases present at different temperatures. The system shows (i) reversible phase separation following the reaction SrCoO3-δ →Sr6 Co5 O15 + Co3 O4 and (ii) hysteresis in oxygen permeability upon cooling but remains reusable.