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A series of Pt/CeO 2 catalysts with different Pt contents were prepared using an incipient wetness impregnation method and tested for CO oxidation. Kinetic study on the catalysts indicated that the reaction rate was independent of the partial pressures of CO and O 2 ( r = k app [CO] 0 [O 2 ] 0 ). The derived reaction pathways involved chemisorption of CO on surface Pt atoms and reacting with lattice oxygen provided by the CeO 2 support at the Pt–CeO 2 interface, suggesting a Mars van-Krevelen type reaction on these catalysts and the interfacial Pt–O–Ce ensembles being the active sites. Also, turnover frequencies (TOFs) calculated based on Pt dispersion and periphery Pt atoms were found to be proportional to the Pt particle size, with the large Pt particles possessing higher TOF than the small ones. Such a trend was interpreted by the important role of the oxygen vacancies via the formation of Pt–Ce–O solid solution, which could accelerate the mobility of lattice oxygen and consequently the activity. [ABSTRACT FROM AUTHOR]

In this study, carbon-coated α-Fe 2 O 3 @Fe 3 O 4 heterostructures were designed and synthesized by a simple ball-milling and an auxiliary rheological phase method combined with carbothermal reduction. Due to the synergistic effect between α-Fe 2 O 3 and Fe 3 O 4 , the carbon-coated α-Fe 2 O 3 @Fe 3 O 4 heterostructures have an excellent electrochemical performance. In order to elucidate the reaction process, the types of gases produced during the pyrolysis of citric acid are preliminarily examined, and the possible chemical reactions are deduced from the experimental results. The Mössbauer spectrum is used to determine the relative ratio of α-Fe 2 O 3 to Fe 3 O 4. As an anode material for lithium ion batteries, a carbon-coated Fe 2 O 3 @Fe 3 O 4 electrode exhibits a high initial discharge/charge capacity of 1462.2/968.2 mAh g−1 and a good reversible capacity (971.5 mAh g−1) at a current density of 0.1 A g−1. Moreover, even after 200 cycles, a reversible capacity of 711.0 mAh g−1 can be maintained at a current density of 0.5 A g−1. • Preparation of carbon-coated Fe 2 O 3 @Fe 3 O 4 heterostructured electrode uses a simple and low-cost method. • The types of reducing gases in the pyrolysis of citric acid were determined and the chemical reaction was inferred. • The possible chemical reaction is deduced from the experiment. • The carbon-coated Fe 2 O 3 @Fe 3 O 4 heterostructured has achieved good rate performance and cycle stability. [ABSTRACT FROM AUTHOR]