Catalytic Activity of Au/$TiO_2$ and Pt/$TiO_2$ Nanocatalysts Prepared with Arc Plasma Deposition under CO Oxidation

  • Jung, Chan Ho (Graduate School of EEWS (WCU) and Nanocentury KI, KAIST) ;
  • Kim, Sang Hoon (Center for Materials Architecturing, Korea Institute of Science and Technology (KIST)) ;
  • Sahu, Nruparaj (Graduate School of EEWS (WCU) and Nanocentury KI, KAIST) ;
  • Park, Dahee (Graduate School of EEWS (WCU) and Nanocentury KI, KAIST) ;
  • Yun, Jung Yeul (Functional Materials Division, Korea Institute of Materials Science (KIMS)) ;
  • Ha, Heonphil (Center for Materials Architecturing, Korea Institute of Science and Technology (KIST)) ;
  • Park, Jeong Young (Graduate School of EEWS (WCU) and Nanocentury KI, KAIST)
  • Published : 2013.02.18

Abstract

We report the catalytic activity of Au/$TiO_2$ and Pt/$TiO_2$ nanocatalysts under CO oxidation fabricated by arc plasma deposition (APD), which is a facile dry process with no organic materials involved. Using APD, the catalyst nanoparticles were well dispersed on $TiO_2$ powder with an average particle size (2~4 nm) well below that of nanoparticles prepared by the sol-gel method (10 nm). We found that the average particle size of the dispersed gold nanoparticles can be controlled by changing the plasma discharge voltage of APD. Accordingly, the amount of loaded gold on the $TiO_2$ powder increased with increasing discharge voltage, but the specific surface area of the Au/$TiO_2$ samples decreased. As for catalytic reactivity, Au/$TiO_2$ showed a higher catalytic activity than Pt/$TiO_2$ in CO oxidation. The catalytic activity of the Au/$TiO_2$ samples showed size dependence where higher catalytic activity occurred on smaller gold nanoparticles. The study suggests that APD is a simple way to fabricate catalytically active nanocatalysts.

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