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...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.展开更多
文摘利用相转化纺丝法制备了Ni O-YSZ中空纤维,在其外表面负载YSZ膜1450℃共烧后形成YSZ/Ni O-YSZ双层中空纤维。阳极孔结构通过芯液(N-甲基砒咯烷酮(NMP)+乙醇)中溶剂NMP的含量来控制。当NMP含量从0、30wt%、50wt%、70wt%增加到100wt%时,阳极的孔结构由指状孔/海绵孔/指状孔三明治结构逐渐成为贯通的指状孔结构,电解质膜致密性、还原后的双层中空纤维的机械强度、阳极电导率逐渐减小,而孔隙率则增加。多孔的阴极Ag涂敷于致密的电解质膜外表面构成微管SOFC。H2/空气微管SOFC的浓差极化随着指状孔长度的增加而减小,当NMP含量为70wt%时,输出性能最佳,最大功率密度为662 m W/cm2(800℃),此时极化阻抗最小。
文摘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.
