Highly carbon- and sulfur-tolerant Sr_2TiMoO_(6-δ) double perovskite anode for solid oxide fuel cells

摘要

Ni-based cermets are most commonly used anode materials for solid-oxide fuel cells (SOFCs), but poor stability operating on hydrocarbon fuels seriously hampers their commercialization due to carbon deposition and sulfur poisoning. Here, we report a carbon- and sulfur-tolerant double perovskite anode Sr2TiMoO6-delta (STMO) combining the characteristics of two simple perovskites of SrTiO3 and SrMoO3. The STMO anode exhibits excellent thermal and chemical compatibility with La0.9Sr0.1Ga0.8Mg0.2O3-delta (LSGM) and Ce0.8Sm0.2O1.9 (SDC) electrolytes in 5% H-2/Ar. The single cell with STMO anode demonstrates good stability and excellent coking resistance and sulfur tolerance in H2S-containing syngas during a 60-h period. The maximum power density (P-max) values of a LSGM-electrolyte-supported single cell with STMO anode are 505 and 275 mW cm(-2) at 850 degrees C in H-2 and H2S-containing syngas, respectively. The electrochemical performance is further improved by impregnation of Pd nanoparticles, where the P-max values achieve 1009 and 586 mW cm(-2) at 850 degrees C under the same conditions, respectively, showing great potential as an anode material for SOFCs operating on H2S-containing syngas. Our study provides a strategy to develop versatile double perovskite materials by combining the relevant characteristics of two separate perovskites. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.