Cost‐effective Synthesis of α‐LiAlO 2 Powders for Molten Carbonate Fuel Cell Matrices

Lithium aluminate (α‐/β‐LiAlO 2 ) particles were fabricated using three methods. The first method used organic glycerin and triethylene glycol which functioned as a catalyst for fabrication of α‐LiAlO 2 particles with Al(OH) 3 and LiOH·H 2 O as the starting materials. As a result of the heat‐treatment of the starting materials, α‐/β‐LiAlO 2 particles could be obtained. The amount of α‐LiAlO 2 particles in α‐/β‐LiAlO 2 increased slightly as more organics were added. Additionally, when synthesised α‐/β‐LiAlO 2 particles were heat‐treated in a CO 2 gas flow, β‐LiAlO 2 was partially transformed to α‐LiAlO 2 . In the second method, molten salts (Li 2 /Na 2 /K 2 CO 3 ) were used as a catalyst to fabricate α‐LiAlO 2 as a major phase, however, this method requires a washing process which can produce unexpected impurities. In the third method, pure α‐LiAlO 2 was obtained by heat‐treatment of cheap sources such as Li 2 CO 3 and Al(OH) 3 at 600–800 °C. The mean particle size (604 nm–11.85 μm) and the specific surface area (3.22–11.4 m 2  g –1 ) of α‐LiAlO 2 were suitable for reinforcing the matrix and tape casting. Lastly, this study examined the effect of CO 2 for the synthesising of α‐LiAlO 2 particles.