Fluorite-type Y2O2/ZrO2（YSZ） powders with the mean particle size of 1.74 μm were synthesized by the citric acid combustion method.Using the prepared YSZ powders,gas-tight hollow fibre membranes were fabricated by a dry-wet spinning process based on the phase inversion technique,followed by sintering at 1 400 ℃ for（4 h.） The gas tightness,porosity,mechanical strength,microstructure and crystalline phase of the hollow fibre membranes were studied.The results indicate that the prepared YSZ hollow fibre membranes are gas-tight while the porosity remains around 23.04% and the bending strength may be up to 322 MPa.The diameter of the pores in the hollow fibres ranges from 60 to 500 nm.XRD spectra show that the fluorite-type phase is kept unchanged,but the crystal size grows bigger after sintering.SEM micrographs show that the prepared YSZ hollow fibre membranes possess an asymmetric structure that includes a dense layer and porous layers,while the inner and outer surfaces are also dense.
