Synthesis of manganese-cobalt spinel via wet chemistry methods and its properties

摘要

Mn1.2Co1.8O4 spinel was synthesized via co-precipitation and EDTA gel processes to optimize the performance of high-quality spinel protective-conducting films deposited on steel interconnects. In the case of co precipitation, in which ammonium hydroxide, ammonium oxalate, and ammonium carbonate were used as precipitating agents, two procedures were applied. In the first one, which was conventional, the precipitating agent was introduced into a mixture of salts, while in the other one, filter paper pre-saturated with a mixture of salts was soaked in the precipitating solution. The calcinated powders prepared via both conventional co precipitation with ammonium hydroxide and EDTA gel processes were pure cubic spinels. The remaining powders had a dual-phase composition with cubic and tetragonal phases. Aside from the sinter obtained from the powder prepared via conventional co-precipitation with ammonium carbonate, which had a composition of Mn1.5Co1.5O4, all sinters were Mn1.2Co1.8O4 cubic spinels. The highest electrical conductivity at 1023 K was observed for the spinet obtained from the powder prepared via conventional co-precipitation with ammonium hydroxide (61.5 S cm-(1)), while the lowest conductivity was measured for the Mn1.5Co1.5O4 spinet (14.7 S The study confirmed that the Mn1.2Co1.8O4 spinel prepared via conventional co-precipitation with ammonium hydroxide is a suitable material for the surface modification of ferritic stainless steel applied in IT-SOFC interconnects.