A new strategy for enhancing the thermo-mechanical and chemical stability of dual-phase mixed ionic electronic conductor oxygen membranes

Abstract

A mixed ionic electronic conductor (MIEC) membrane with thermo-mechanical and chemical stability has been developed. A fluorite-rich dual-phase composite (80 vol% Ce_0.9Gd_0.1O_2−δ–20 vol% La_0.7Sr_0.3MnO_3−δ) based on the chemically stable pure electronic conductor oxide (LSM) and doped-ceria (GDC) was used as the membrane material. By introducing a thermo-mechanically and chemically stable coating material (Pr₂NiO_4+δ) to the membranes, this study proposes a new strategy for enhancing the overall stability of the oxygen permeation ceramic membrane. The stability of the dual-phase membrane was assessed in the presence of CO₂ at intermediate temperatures, and thermal cycling tests were performed to evaluate its performance under extreme conditions. The dual-phase membrane with Pr₂NiO_4+δ coating layer not only showed remarkable stability in a pure CO₂ atmosphere but also exhibited thermo-mechanical stability during rapid thermal cycling tests (cooling and heating rate: 30 °C min⁻¹).