環境・エネルギー問題と膜 メンブレーンリアクターとしての固体酸化物形燃料電池

Abstract

Characteristic features of solid oxide fuel cells have been reviewed with an emphasis on their features as membrane reactor. In particular, the mass transfer characteristics of electrolytes and interconnect materials have been discussed to clarify the appropriateness as SOFC electrolyte and interconnects. For electrolyte, the low electron conductivity in addition to the high oxide conductivity is essential. Since the relatively large electron contribution for doped ceria, these materials cannot be used as SOFC electrolyte, whereas lanthanum gallate-based electrolyte exhibits excellent properties particularly at low temperatures. For interconnect materials, lanthanum chromite exhibits excellent properties. The oxygen permeation through the calcium doped lanthanum chromite has been identified as surface reaction limited process, which allows to use as thin interconnect.