a Based on a simple colloid deposition method, a series of Pt/FeOx catalysts were prepared using 3-4 nm Pt colloid nanoparticles and FeOx with different microstructure (i.e. the structure and surface properties). FeOx support was obtained via a thermal-treatment method, which enables the tailoring of FeOx from ferrihydrite to α-Fe2O3 and the amount of hydroxides on the surface of FeOx decreases gradually with the phase changing. Over an optimized Pt/FeOx, CO could be completely converted at room temperature (298 K) and a relatively high space velocity (1.2╳10 5 mL·g -1 ·h -1 ). The correlation between the microstructure of FeOx support and the CO oxidation performance of resultant Pt/FeOx catalyst was investigated. Although the oxidation of Pt nanoparticles is inevitable in the process of Pt-loading, relatively large amounts of Pt 0 species can be preserved on the FeOx support possessing abundant surface hydroxides. In-situ DRIFT shows that the surface hydroxides of FeOx could also participate in the catalytic process: they could react with CO absorbed on Pt 0 sites and then recover easily in the co-presence of molecular oxygen and water gas. These results show that intrinsic properties of FeOx support not only affect the oxidation state of supported Pt nanoparticles in the preparation process, but also provide new active sites in the catalytic process. FeOx support possessing abundant surface hydroxides is suitable for preparing high performance Pt/FeOx catalyst for low-temperature CO oxidation.

A composite of Fe3O4 nanoparticles anchored on a carbon support (Fe3O4/C), possessing both superparamagnetism and molecular oxygen activating properties, was prepared by an ammonia‐assisted precipitation method. Fe3O4/C could catalyze the selective oxidation of various benzyl alcohols with air as the oxidant source, and could be easily separated and recycled with an external magnet. The small particle size and the interaction between the Fe3O4 nanoparticles and carbon support endow the Fe3O4/C catalyst with relatively high reducibility. Its oxidation state is easy to change. This intrinsic property of the Fe3O4 nanoparticles could be responsible for the high activity of Fe3O4/C in the aerobic oxidation of alcohols.

CeO nanorods anchored on mesoporous carbon exhibit high activity and stability in aerobic oxidative coupling of alcohols and amines to imines. The abundant surface Ce and the suitable interaction between CeO nanorods and the carbon support should be responsible for the excellent catalytic behaviors.

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