An anode-supported micro-tubular solid oxide fuel cell with redox stable composite cathode

A NiO-YSZ anode-supported hollow fiber solid oxide fuel cell (HF-SOFC) has been fabricated with redox stable (La0.75Sr0.25)(0.95)Cr0.5Mn0.5O3-delta-Sm0.2Ce0.8O1.9-YSZ (LSCM-SDC-YSZ) composite cathode. The characterization of NiO-YSZ hollow fibers prepared by the phase inversion method is focused on the microstructure, porosity, bending strength and electrical conductivity. A thin YSZ electrolyte membrane (about 10 mu m) can be prepared by a vacuum-assisted dip-coating process and is characterized in terms of microstructure and gas-tightness. The performance of the as-prepared HF-SOFC is investigated at 750-850 degrees C with humidified H-2 as fuel and ambient air as the oxidant. The peak power densities of 513, 408 and 278 mW cm(-2) can be obtained at 850, 800 and 750 degrees C, respectively, and the corresponding interfacial polarization resistances are 0.14, 0.29 and 0.59 Omega cm(2). The high performance at intermediate-to-high temperatures could be attributed to thin electrolyte and proper composite cathode with low interfacial polarization resistance. The low interfacial polarization resistance suggests potential applications of LSCM-SDC-YSZ composite oxides as the redox stable cathode. This investigation indicates that the redox stable LSCM-SDC-YSZ is a promising cathode material system for the next generation YSZ-based HF-SOFC. The results will be expected to open up a new phase of the research on the micro-tubular SOFCs. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.