Micro-tubular solid oxide electrolysers for electrochemical CO2 reduction of the form Ni-YSZ vertical bar YSZ vertical bar YSZ-LSM vertical bar LSM have been fabricated using a two-step method: dual layer co-extrusion phase inversion to produce electrode-supported vertical bar electrolyte precursors and subsequent coating with the outer electrode, whereby each step was followed by (co-)sintering. The microstructures and physical properties of the fibres were characterized and the electrochemical performance of the fabricated electrolysers determined. Electrolyte thicknesses of 19 (+/- 2), 26 (+/- 2) and 49 (+/- 3) mm were achieved. Electrolysis performance increased with increasing temperature (700-800 degrees C) and with decreasing electrolyte thickness. The maximum performance achieved was 1.0 A cm(-2) at 1.8 V cell potential difference at 800 degrees C for a 15 mm electrolyte. Electrical impedance spectroscopy revealed that only 5-28% of the ohmic polarization resistance was due to the electrolyte resistance; most of the resistance was due to electrical connections and contact potential losses. The feasibility to operate the solid oxide cells in electrolysis and fuel cell modes was demonstrated, revealing that no unique gas composition existed that would optimise the performance in both modes simultaneously.
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机译：Ni-YSZ垂直棒YSZ垂直棒YSZ-LSM垂直棒LSM制成的用于电化学还原CO2的微管固体氧化物电解槽采用两步法制造：双层共挤出相转化产生电极支撑的垂直电解质前体，随后用外部电极涂覆，由此在每个步骤之后进行（共）烧结。表征了纤维的微观结构和物理性质，并确定了所制备的电解槽的电化学性能。电解质厚度达到19（+/- 2），26（+/- 2）和49（+/- 3）mm。电解性能随温度（700-800摄氏度）的升高和电解质厚度的减小而提高。对于15毫米电解质，在800摄氏度，1.8 V电池电势差下，可实现的最大性能为1.0 A cm（-2）。电阻抗光谱法表明，只有5-28％的欧姆极化电阻是由电解质电阻引起的;大部分电阻是由于电气连接和接触电势损失造成的。证明了在电解和燃料电池模式下操作固体氧化物电池的可行性，表明没有独特的气体成分可以同时优化两种模式下的性能。
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