Electrolyte Thickness Control and Its Effect on YSZ/Ni-YSZ Dual-layer Hollow Fibres

doi:10.3724/SP.J.1077.2013.12755

Abstract

Abstract: Electrolyte/anode (YSZ/NiO-YSZ) dual-layer hollow fibres were developed by a co-spinning process based on phase inversion technique for fabrication of micro tubular solid oxide fuel cells (MT-SOFCs). After being calcined at 1450℃ in ambient air and reduced at 700℃ in H2 for 4 h, the precursors were transformed into dual layer YSZ/Ni-YSZ hollow fibers. Full MT-SOFCs were fabricated by dip-coating with La_0.8Sr_0.2MnO_3-δ (LSM) ink on the outer surface of YSZ/NiO-YSZ dual layer hollow fibers and sintering at 1200℃. The results show that the YSZ membranes of the dual-layer hollow fibers possess thicknesses of 6, 13, 18 and 28 μm when the spinning rates of electrolyte dopes are 0.5, 1, 1.5 and 2 mL/min and the anode dope keeps on a constant rate of 10 mL/min. The bending strength and the gas-tightness of the dual-layer hollow fibers increase with the increase of electrolyte thickness. However, the electrical conductivity and porosity of the dual-layer hollow fibers are less influenced by YSZ thickness. The maximum power density of single MT-SOFC with an electrolyte layer of 28 μm is 75 mW/cm², while the output of an MT-SOFC with a 6 μm-thick YSZ membrane is up to 329 mW/cm², both operated at 800?℃ using 20 mL/min H₂ as fuel and 30 mL/min air as oxidant.

Key words: dual-layer hollow fibre (DL-HF), YSZ electrolyte membrane, phase-inversion method, micro tubular solid oxide fuel cells (MT-SOFCs), co-spinning-sintering

CLC Number:

TQ174

GONG Xun, MENG Xiu-Xia, YANG Nai-Tao, TAN Xiao-Yao, YIN Yi-Mei, MA Zi-Feng. Electrolyte Thickness Control and Its Effect on YSZ/Ni-YSZ Dual-layer Hollow Fibres[J]. Journal of Inorganic Materials, 2013, 28(10): 1108-1114.

References

[1] Shao Z, Haile S M, Ahn J, et al. A thermally self-sustained micro solid-oxide fuel-cell stack with high power density. Nature, 2005, 435(7043): 795-798.

[2] Atkinson A, Barnett S, Gorte R J, et al. Advanced anodes for high-temperature fuel cells. Nature, 2004, 3(1): 17-27.

[3] Ye X F, Wang S R, Hu Q, et al. Improvement of multi-layer anode for direct ethanol solid oxide fuel cells. Electrochemistry Communications, 2009, 11(4): 823-826.

[4] Yang C L, Li W, Zhang S Q, et al. Fabrication and characterization of an anode-supported hollow fiber SOFC. J. Power Sources, 2009, 187(1): 90.

[5] Wang H D, Liu J. Effect of anode structure on performance of cone-shaped solid oxide fuel cells fabricated by phase inversion. Int. J. Hydrogen Energy, 2012, 37(5): 4339-4345.

[6] Kendall K. Progress in Microtubular solid oxide fuel cells. Int. J. Appl. Ceram. Tech., 2010, 7(1): 1-9.

[7] Suzuki T, Yamaguchi T, Fujishiro Y, et al. Fabrication and characterization of micro tubular SOFCs for operation in the intermediate temperature. J. Power Sources, 2006, 160(1): 73-77.

[8] Kikuta K, Kubota C, Takeuchi Y, et al. Fabrication and characterization of microtubular and flatted ribbed SOFCs prepared by the multi-dip coating and co-firing. J. Eur. Ceram. Soc., 2010, 30(4): 927-931.

[9] Tan X Y, Yin W N, Meng B, et al. Preparation of electrolyte membranes for micro tubular solid oxide fuel cells. Sci.China, Ser. B., 2008, 51(9): 808-812.

[10] Othman M H D, Wu Z T, Droushiotis N, et al. Single-step fabrication and characterisations of electrolyte/anode dual-layer hollow fibres for micro-tubular solid oxide fuel cells. J. Power Sources, 2010, 351(1/2): 196-204.

[11] Othman M H D, Droushiotis N, Wu Z T, et al. Electrolyte thickness control and its effect on electrolyte/anode dual-layer hollow fibres for micro-tubular solid oxide fuel cells. J. Power Sources, 2010, 365(1/2): 382-388.

[12] Droushiotis N, Wu Z T, Kelsall G, et al. High-performance anode- supported microtubular SOFC prepared from single-step- fabricated dual-layer hollow fibers. Adv. Mater., 2011, 23(21): 2480-2483.

[13] Evans A, Bieberle-Hütter A, Jennifer L M, et al. Review on microfabricated micro-solid oxide fuel cell membranes. J. Power Sources, 2009, 194(1):119-129.

[14] Timurkutluk B, Celik S, Toros S, et al. Effects of electrolyte pattern on mechanical and electrochemical properties of solid oxide fuel cells. Ceram. Int., 2012, 38(7): 5651-5659.

[15] Jacobson A J. Materials for solid oxide fuel cells. Chem. Mater., 2010, 22(3): 660-674.

[16] Ko C, Kerman K, Ramanathan S. Ultra-thin film solid oxide fuel cells utilizing un-doped nanostructured zirconia electrolytes. J. Power Sources, 2012, 213(1): 343-349.

[17] LWI Ze, ZHU Qing-Shan, HAN Min-Fang. Fabracation and performance of direct methane SOFC with a Cu-CeO2-based anode. Acta Phys. Chim. Sin., 2010, 26(3): 583-588.

[18] Zhao Xiang, Wang Feng-Hui, Wang Xia, el al. Effect of residual stresses on elastoplastic properties of SOFC by nanoindentation approach. Joural of Inorganic Materials, 2011, 26(4): 393-397.

[19] Tan X, Liu Y, Li K. Mixed conducting ceramic hollow-fiber membranes for air separation. AIChE J, 2005, 51(7): 1991-2000.

[20] Droushiotis N, Doraswami U, Kanawka K, et al. Characterization of NiO–yttria stabilised zirconia (YSZ) hollow fibres for use as SOFC anodes. Solid State Ionics, 2009, 180(17/18/19): 1091-1099.

[21] Yang N T, Tan X Y, Meng X X, et al. Fabrication of Anode Supported Micro Tubular SOFCs by Dip-coating Process on NiO/YSZ Hollow Fibers. 216th ECS Meeting in Vienna, Austria, 2009, 25(2): 811-888.

[22] Anselmi-Tamburini, Chiodelli G, Arimondi M, et al. Electrical properties of Ni/YSZ cermets obtained through combustion synthesis. Solid State Ionics, 1998, 110 (1/2): 35-43.

[23] Li Chang-Jiu, Li Cheng-Xin, Xing Ya-Zhe, et al. Influence of YSZ electrolyte thickness on the characteristics of plasma-sprayed cermet supported tubular SOFC. Solid State Ionics, 2006, 177(19-25): 2065-2069.