Mn, Ni and Cu cobaltite spinels were synthesized by coprecipitation, characterized and evaluated in the total oxidation of methane. To gain a deeper insight into their catalytic behavior, their electrical conductivity was studied as a function of temperature and oxygen partial pressure, and was followed with time during sequential exposures to different gases in conditions close to those used for the catalytic tests. The Ni cobaltite is in a metallic conductivity state and cannot be reduced in the reaction conditions, suggesting that it functions via a suprafacial mechanism. The Cu cobaltite behaves as a p-type semiconductor, but it is not reduced under the reaction mixture at the reaction temperature of 350 °C, suggesting that, at least in these conditions, the suprafacial mechanism is operating. The Mn cobaltite has an n-type semiconducting character and is reduced in the reaction conditions, suggesting that a heterogeneous redox mechanism is involved.

Mn，Ni和Cu钴尖晶石通过共沉淀法合成，表征和评估甲烷的总氧化程度。为了更深入地了解它们的催化行为，研究了它们的电导率与温度和氧分压的关系，并在与催化试验所用条件相近的条件下，依次暴露于不同的气体中，并随时间进行跟踪。镍钴矿处于金属导电状态，并且在反应条件下不能被还原，表明它通过表面机制起作用。铜钴矿表现为p型半导体，但是在反应混合物中在350℃的反应温度下它并未还原，这表明至少在这些条件下，表面机理是起作用的。