We report mesoporous Co‐Al oxide nanosheets (Co_xAl‐Ns, where x denotes the Co/Al ratio in the samples) prepared by calcination of CoAl‐hydrotalcite and subsequent alkaline treatment. X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy measurements show that the prepared Co‐Al oxide nanosheets (Co_xAl‐Ns) are very thin (10–15 nm) and exhibit high mesoporosity (3–5 nm). Catalytic CO oxidation tests reveal that the Co_xAl‐Ns exhibit excellent catalytic performances at relatively low temperatures: for example, the Co_2.5Al‐Ns catalyst could achieve 99% CO conversion at −98°C. Kinetic studies and experimental investigations indicate that the high activity of the Co_2.5Al‐Ns sample is strongly related to the abundance of active sites associated with the large Brunauer–Emmett–Teller surface area. The Co_2.5Al‐Ns catalyst also achieves full conversion of CO in tests performed with a gas mixture simulating automobile exhaust gas at 200°C. After loading the Co_2.5Al‐Ns on a porous ceramic substrate, the obtained Co_2.5Al‐Ns/PC shows high activity and stability in CO oxidation process. These features are potentially important for future industrial applications of these catalysts.

中文翻译：

---

介孔Co-Al氧化物纳米片作为CO氧化的高效催化剂

我们报告了通过煅烧CoAl-水滑石和随后的碱处理制备的介孔Co-Al氧化物纳米片（Co _x Al-Ns，其中x表示样品中的Co / Al比）。X射线衍射，扫描电子显微镜，透射电子显微镜和X射线光电子能谱测量表明，制备的Co-Al氧化物纳米片（Co _x Al-Ns）非常薄（10–15 nm），并具有较高的介孔率（ 3-5 nm）。催化CO氧化测试表明Co _x Al-Ns在相对较低的温度下表现出出色的催化性能：例如Co _2.5Al-Ns催化剂可在-98°C下实现99％的CO转化率。动力学研究和实验研究表明，Co _2.5 Al-Ns样品的高活性与与大Brunauer-Emmett-Teller表面积相关的大量活性位密切相关。Co _2.5 Al-Ns催化剂在模拟汽车废气在200°C的混合气体中进行的测试中也实现了CO的完全转化。将Co _2.5 Al-Ns负载在多孔陶瓷基底上后，所得Co _2.5 Al-Ns / PC在CO氧化过程中显示出高活性和稳定性。这些特征对于这些催化剂的未来工业应用潜在重要。