화학공학소재연구정보센터
Journal of Power Sources, Vol.213, 140-144, 2012
Calcium doped Y3Fe5O12 as a new cathode material for intermediate temperature solid oxide fuel cells
Calcium doped yttrium iron garnet, Y2.5Ca0.5Fe5O12-delta (YCFO), was studied as a new cathode material for intermediate temperature solid oxide fuel cells. Low polarization resistance of 0.55 Omega cm(2) at 650 degrees C was realized with the use of YCFO-Ce0.8Sm0.2O1.9 (SDC, 40 wt.%) composite electrode. An investigation over limiting steps of the cathode reaction suggests that oxygen ion diffusion, oxygen dissociative adsorption, and gas-phase diffusion might be the rate-limiting steps for the YCFO-SDC cathode. Of a single cell using the YCFO-SDC composite cathode, the polarization resistance reduces to as low as 0.14 Omega cm(2) measured at 650 degrees C, and the maximum power density reaches 438 mW cm(-2) with a 40 mu m - thick SDC electrolyte. (C) 2012 Elsevier B.V. All rights reserved.