Evaluation of Ni/SDC as anode material for dry CH_4 fueled Solid Oxide Fuel Cells

摘要

A Ni/Sm_(0.2)Ce_(0.8)O_(1.9) (SDC) composite was employed as anode material for direct electrochemical oxidation (DEO) of dry CH4_ in a solid oxide fuel cell. The anodic performance was investigated at temperatures between 600 ℃ and 700 ℃ using SDC as electrolyte material and Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) (BSCF) as cathode material. The single cell exhibited maximum power densities of 671 mW cm~(-2), 494 mW cm~-2 and 305 mW cm~(-2) in dry CH4 at 700 ℃, 650 ℃ and 600 ℃, respectively. Remarkably, at 700 ℃ the power density in CH_4 was higher than in H_2, thanks to the carbon tolerance of the anode. Durability tests under constant 300 mA output current showed only 3.7% performance loss after 72 h operation. The results demonstrate that Ni/SDC can be used as anode for the DEO of dry CH_4 even at temperatures as low as 600 ℃.