The skutterudite CoSb₃ is a well-known thermoelectric material widely used to produce electricity from heat. This material is commonly employed under vacuum but in a near future it is expected to be used at high temperatures under oxidative atmospheres, e.g. in air. The lifetime of the material may be affected by the oxidative environment, considerably limiting the use of the thermoelectric equipment. The present research describes the degradation mechanisms of CoSb₃ from oxidation experiments carried out under a flow of synthetic air at 800 K. The skutterudite material is progressively oxidized after 15 h, 50 h, 100 h and 1000 h of treatment, producing three oxides on the CoSb₃ surface (CoSb₂O₄/CoO·Sb₂O₃, Sb₂O₄ and CoSb₂O₆). These three oxides have different growth kinetics and they are produced in various amounts as a function of the oxidation time.

Next, as a solution for an appropriate oxidation protection, this work explores the chemical vapor deposition (CVD) process named pack cementation to synthesize a protective coating on CoSb₃. This process produces a surface layer made of aluminum antimonide (AlSb) and cobalt aluminide (Al₉Co₂). The oxidation experiments carried out on the coated CoSb₃ highlight the protective properties of this innovative surface layer. The coating is a protective barrier against oxygen that keeps the CoSb₃ substrate unaffected by the flow of air at 800 K for 1000 h. Consequently, pack cementation is an efficient process to synthesize a protective surface layer that makes CoSb₃ usable under oxidative environments.

方钴矿CoSb ₃是一种众所周知的热电材料，广泛用于从热中发电。该材料通常在真空下使用，但在不久的将来，预计将在氧化气氛（例如空气）中的高温下使用。材料的寿命可能会受到氧化环境的影响，从而大大限制了热电设备的使用。本研究描述了在800 K的合成空气流下进行的氧化实验所产生的CoSb ₃的降解机理。该方钴矿材料经过15 h，50 h，100 h和1000 h的处理后逐渐被氧化，在该处产生三种氧化物。 CoSb ₃表面（CoSb ₂ O ₄ / CoO·Sb₂ O ₃，Sb ₂ O ₄和CoSb ₂ O ₆）。这三种氧化物具有不同的生长动力学，并且根据氧化时间以不同的量产生。

接下来，作为适当氧化保护的解决方案，这项工作探索了化学气相沉积（CVD）工艺（称为填充胶结），以在CoSb ₃上合成保护涂层。该过程产生了由锑化铝（AlSb）和铝化钴（Al ₉ Co ₂）制成的表面层。在涂覆的CoSb ₃上进行的氧化实验突出了这种创新表面层的保护性能。该涂层是防止氧气的保护性屏障，可保持CoSb ₃基材不受800 K 1000 h空气流的影响。因此，填充胶结是合成保护层的有效方法，该保护层可制成CoSb ₃ 可在氧化环境下使用。