A thermoelectric generator is a powerful system used to produce electricity by the action of heat. The development of nanostructured thermoelectric materials is widespread with the objective to improve their efficiency. However, if these materials are used at high temperatures under oxidative atmosphere (e.g., in air), they may suffer degradation in service, drastically decreasing their lifespan. This work investigates the oxidation behavior of an innovative skutterudite material made of cerium, iron, cobalt and antimony (Ce0.75Fe3CoSb12) either microstructured or nanostructured. For that purpose, several oxidation experiments are carried out under a flow of synthetic air at 650 K (15 h, 50 h and 100 h). The oxide layers formed on surface are observed, and their characteristics (chemical composition, thickness, structure) are compared to those obtained with microstructured Ce0.75Fe3CoSb12 samples. As a result, it is observed that the nanostructuring of the skutterudite materials slightly slow down the oxidation reactions in air. Consequently, the nanostructured Ce0.75Fe3CoSb12 is established to be a promising thermoelectric material for use in oxidative environments.

中文翻译：

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方钴矿材料 Ce0.75Fe3CoSb12 的氧化行为

热电发电机是一种强大的系统，用于通过热量的作用发电。纳米结构热电材料的开发广泛用于提高其效率。然而，如果这些材料在氧化气氛（例如，在空气中）的高温下使用，它们在使用中可能会退化，从而大大缩短其使用寿命。这项工作研究了由铈、铁、钴和锑 (Ce0.75Fe3CoSb12) 制成的创新方钴矿材料的氧化行为，无论是微结构还是纳米结构。为此，在 650 K（15 小时、50 小时和 100 小时）的合成空气流下进行了几次氧化实验。观察表面形成的氧化层，以及它们的特性（化学成分、厚度、结构）与用微结构 Ce0.75Fe3CoSb12 样品获得的那些进行比较。结果，观察到方钴矿材料的纳米结构稍微减慢了空气中的氧化反应。因此，纳米结构的 Ce0.75Fe3CoSb12 被认为是一种用于氧化环境的有前途的热电材料。