Development of cobalt doped lithiated NiO nano-composites and hot corrosion testing of LiAlO2 matrices for molten carbonate fuel cell (MCFC) applications

Dissolution of conventional NiO cathode for MCFCs is a major hurdle in its commercialization. Recent studies have shown an increase in exchange current density of cobalt doped cathode materials developed under controlled conditions. In this work, water-based solution has been used to synthesize lithiated NiO and cobalt doping has been done to improve the electrical conductivity of cathode material. Lower-cost precursors have been used with reduced calcination temperature of 650 °C for material synthesis. Structural characterization tools such as XRD, SEM, etc. have been used to investigate into high efficiency cobalt doped lithiated NiO prepared with various process parameters. Moreover, electrical properties show an improvement in electrical conductivity with a value of 12.16 Scm−1. Meanwhile, highly pure tetragonal nano-LiAlO2 matrix, stable at high operating temperatures, has been in-house developed by wet-mixing method. The tolerance of LiAlO2 pellets is further reported in corrosive molten salt environment at 650 °C using Li/Na/K, Li/Na and Li/K carbonates mixtures at a loading rate of 15 mg/cm2. Studies revealed that Na2CO3 had a pronounced impact on chemical and structural stability of LiAlO2 causing formation of NaAlO2 impure phase. However, potassium containing mixture had a minimal influence on matrix material and treated pellet remained chemically unaffected.