TY - JOUR
T1 - Dynamical behaviour of PtRh(100) alloy surface during dissociative adsorption of NO and reaction of NO with H2
AU - Hirano, Hideki
AU - Yamada, Taro
AU - Tanaka, Ken ichi
AU - Siera, Jacobus
AU - Nieuwenhuys, B. E.
N1 - Funding Information:
The authors acknowledge the Ministry of Economic Affairs of the Netherlands for their support of our collaboration program, and one of the authors (J. Siera) worked at the ISSP of the University of Tokyo under the assistance of Japan-Netherlands Institute. This work has been supported by the Ministry of Education of Japan by the Grant-in-aid (No. 01609003) for Scientific Research on Priority Areas.
PY - 1989/11/2
Y1 - 1989/11/2
N2 - When a clean Pt-Rh(100) alloy surface was exposed to NO at T > 440 K, the LEED pattern changed sequentially as p(1 × 1) → c(2 × 2) → c(2 × 2) + p(3 × 1) → p(3 × 1), where the c(2 × 2) pattern appeared immediately after the exposure to NO. In contrast to this, the appearance time for the p(3 × 1) depends strongly on the initial Rh concentration on the surface adjusted by annealing. When the p(3 × 1) surface was exposed to H2 by mixing H2 into NO gas, the AES intensity of O(a) decreased and of N(a) increased markedly and the LEED pattern changed from p(3 × 1) to c(2 × 2). These results suggest that N(a) has equal affinity to Pt and Rh atoms so that the N(a) does not distinguish the Pt and Rh sites on the alloy surface. On the other hand, O(a) makes a stronger bond with Rh atoms so that Rh atom segregation onto the surface is induced. By reacting randomly distributed Rh atoms on the Pt-Rh(100) surface with oxygen, a surface compound in a p(3 × 1) arrangement is built on the surface.
AB - When a clean Pt-Rh(100) alloy surface was exposed to NO at T > 440 K, the LEED pattern changed sequentially as p(1 × 1) → c(2 × 2) → c(2 × 2) + p(3 × 1) → p(3 × 1), where the c(2 × 2) pattern appeared immediately after the exposure to NO. In contrast to this, the appearance time for the p(3 × 1) depends strongly on the initial Rh concentration on the surface adjusted by annealing. When the p(3 × 1) surface was exposed to H2 by mixing H2 into NO gas, the AES intensity of O(a) decreased and of N(a) increased markedly and the LEED pattern changed from p(3 × 1) to c(2 × 2). These results suggest that N(a) has equal affinity to Pt and Rh atoms so that the N(a) does not distinguish the Pt and Rh sites on the alloy surface. On the other hand, O(a) makes a stronger bond with Rh atoms so that Rh atom segregation onto the surface is induced. By reacting randomly distributed Rh atoms on the Pt-Rh(100) surface with oxygen, a surface compound in a p(3 × 1) arrangement is built on the surface.
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U2 - 10.1016/0039-6028(89)90327-0
DO - 10.1016/0039-6028(89)90327-0
M3 - Letter
AN - SCOPUS:0000147401
SN - 0039-6028
VL - 222
SP - L804-L808
JO - Surface Science
JF - Surface Science
IS - 1
ER -