PdFe/CeO2 bimetal catalysts prepared by dual arc-plasma deposition.

Bimetal nanoparticles of PdFe were deposited onto CeO2 by using dual arc-plasma to study their structures and catalytic properties for CO oxidation. Highly dispersed uniform nanoparticles with the average size of about 2nm were successfully obtained. By synchronizing two pulsed arc-plasmas, single bimetal nanoparticles containing both Pd and Fe could be formed, but asynchronous pulsing yielded mixtures of each metal nanoparticle. In accordance with the structural difference, the PdFe bimetal nanoparticle on CeO2 was found to stabilize metallic states of Pd and Fe and therefore exhibited higher catalytic activities for CO oxidation. The same trend was observed after thermal ageing at 900°C for 25h in a stream of 10% H2O in air; PdFe/CeO2 prepared under the synchronous pulse condition showed the higher activity than Pd/CeO2 and asynchronous PdFe/CeO2 due to abundance of metallic Pd. [Copyright &y& Elsevier]