Enhanced performance of Fe2O3 doped yttria stabilized zirconia hollow fiber membranes for water treatment

Abstract Fe 2 O 3 powders were introduced as sintering aid to fabricate yttria-stabilized zirconia (YSZ) hollow fiber membranes using a combined wet-spinning and post-sintering method. The obtained Fe 2 O 3 -YSZ hollow fiber membranes show enhanced performance for water treatment with fine crystal structure in terms of bending strength and pure water permeability. Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and thermogravimetric analysis (TGA) along with mechanical tests were employed to investigate the structural evolution in the sintering process and the effect of Fe 2 O 3 . It is suggested that the Fe 2 O 3 dopants dissolve into YSZ at elevated temperatures, providing defect sites and vacancies for fast ion migration, favoring for densification and grain growth of the YSZ, which yields dense microstructures of fine crystallites at relatively low sintering temperature. The Fe 2 O 3 -YSZ hollow fiber membranes sintered at 1150 °C show a 3-fold increase of the permeate flux of pure water ( F ) (743 L m −2  h −1 ) along with comparable bending strength (152 MPa) compared to pure YSZ membranes. This modified method can reduce sintering costs and therefore fabrication costs which should pave the way for scale-up production for ceramic hollow fiber membranes.