Preparation and Properties of (YCa)(TiMn)O(3−δ) Ceramics Interconnect of Solid Oxide Fuel Cells

(YCa)(TiMn)O(3–δ) ceramics prepared using a reaction-sintering process were investigated. Without any calcination involved, the mixture of raw materials was pressed and sintered directly. Y(2)Ti(2)O(7) instead of YTiO(3) formed when a mixture of Y(2)O(3) and TiO(2) with Y/Ti ratio 1/1 were sintered in air. Y(2)Ti(2)O(7), YTiO(2.085) and some unknown phases were detected in Y(0.6)Ca(0.4)Ti(0.6)Mn(0.4)O(3–δ). Monophasic Y(0.6)Ca(0.4)Ti(0.4)Mn(0.6)O(3–δ) ceramics were obtained after 1400–1500 °C sintering. Dense Y(0.6)Ca(0.4)Ti(0.4)Mn(0.6)O(3–δ) with a density 4.69 g/cm(3) was observed after 1500 °C/4 h sintering. Log σ for Y(0.6)Ca(0.4)Ti(0.6)Mn(0.4)O(3–δ) increased from –3.73 Scm(–1) at 350 °C to –2.14 Scm(–1) at 700 °C. Log σ for Y(0.6)Ca(0.4)Ti(0.4)Mn(0.6)O(3–δ) increased from –2.1 Scm(–1) at 350 °C to –1.36 Scm(–1) at 700 °C. Increasing Mn content decreased activation energy E(a) and increased electrical conductivity. Reaction-sintering process is proved to be a simple and effective method to obtain (YCa)(TiMn)O(3–δ) ceramics for interconnects in solid oxide fuel cells.