Comparative study on the performance of co-extruded hollow fiber solid oxide fuel cell fuelled with hydrogen and methane

摘要

In this study, the effects of two fuel types, i.e., hydrogen and methane on the electrochemical performance of the co-extruded triple layer hollow fiber, were systemically studied. The triple layer hollow fiber consisted of electrolyte/active functional layer (AFL)/anode was fabricated by single-step phase-inversion-based co-extrusion technique prior to the sintering process at temperature range of 1400 to 1500 degrees C. The hollow fibers were characterized by three-point bending test, gas tightness test, and scanning electron microscope (SEM). The electrochemical performance test was carried out at temperatures of 700-800 degrees C by flowing fuel at 20 ml/min. Based on the results attained, the gas tightness and bending test are improved by the increase of sintering temperature. SEM results show that the finger-like morphology length around 100 mu m is obtained. In addition, the AFL layer located in the middle layer of the hollow fiber has its own finger like which forms sandwich-like structure with the anode layer. The open circuit voltage is recorded at 1.05 V with the highest power density obtained at 0.6 W cm(-2) by using hydrogen. By changing the fuel into methane gas, the highest power density is achieved at 0.8 W cm(-2). This is due to the methane that carries more hydrogen molecule. This indicates that the methane fuel can be utilized in hollow fiber SOFC systems.