화학공학소재연구정보센터
Journal of Power Sources, Vol.270, 587-593, 2014
Avoiding chromium transport from stainless steel interconnects into contact layers and oxygen electrodes in intermediate temperature solid oxide electrolysis stacks
We investigated the ability of (La0.8Sr0.2)(Mn0.5Co0.5)O3-delta (LSMC) and La(Ni0.6Fe0.4)O3-delta (LNF) contact coatings to avoid the transport of Cr from steel interconnects to solid oxide electrolysis electrodes, especially to the anode. The transport of chromium from commercial Crofer 22 APU (ThyssenKrupp) and K41X (AISI441, Aperam Isbergues) steels through LSMC and LNF contact coatings into adjacent (La0.8Sr0.2) MnO3-delta (LSM) oxygen electrodes was investigated in an oxygen atmosphere at 700 degrees C. Chromium concentrations of up to 4 atom% were detected in the contact coatings after thermal treatments for 3000 h, which also lead to the presence of chromium in adjacent LSM electrodes. Introduction of a dense (Co,Mn)(3)O-4 coating between steel and contact coating was necessary to prevent the diffusion of chromium into contact coatings and electrodes and should lead to extended stack performance and lifetime. (C) 2014 Elsevier B.V. All rights reserved.