A SEARCH FOR SUITABLE COATING MATERIALS ON SEPARATOR PLATES FOR MOLTEN-CARBONATE FUEL-CELLS

Stainless steel separator plates in molten carbonate fuel cells need t o be protected against corrosion, preferably by a coating. We select a suitable coating material by an elimination procedure. First we argue that nonoxide metal/non-metal ceramic coatings are preferred. Then we select the metallic and non-metallic components for the ceramic coati ng. Selected non-metallic components of the most promising ceramics ar e B, C, N, Si and P. Metals eliminated in the elimination procedure ha ve oxides or mixed oxides with eutectics below the MCFC operating temp erature of 700 degrees C. Metals selected as components of the most pr omising ceramics are Ti, Y, Nb, La, Ce, Nd, I-If and Ta. Thus the bori des, carbides, nitrides, silicides or phosphides of these selected met als may be suitable coating materials. Stability experiments show that TiN, TiC and Ce-based ceramics are promising coating materials. (C) 1 997 Elsevier Science Ltd.