Visualization of Surfaces of Pt and Ni Model Catalysts in Reactive Environments Using Ambient Pressure High Temperature Scanning Tunneling Microscopy and Understanding the Restructurings of Surfaces of Model Metal Catalysts under Reaction Conditions at Near Ambient Pressure

2012 ◽  
Vol 117 (2) ◽  
pp. 971-977 ◽  
Author(s):  
Luan Nguyen ◽  
Fang Cheng ◽  
Shiran Zhang ◽  
Franklin (Feng) Tao
Keyword(s):  
High Temperature ◽  
Scanning Tunneling Microscopy ◽  
Ambient Pressure ◽  
Metal Catalysts ◽  
Model Catalysts ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Reaction Conditions ◽  
Temperature Scanning

IN-SITU HIGH-TEMPERATURE SCANNING-TUNNELING-MICROSCOPY STUDIES OF TWO-DIMENSIONAL ISLAND-DECAY KINETICS ON ATOMICALLY SMOOTH TiN(001)

2000 ◽  
Vol 07 (05n06) ◽  
pp. 589-593 ◽  
Author(s):  
S. KODAMBAKA ◽  
V. PETROVA ◽  
A. VAILIONIS ◽  
P. DESJARDINS ◽  
D. G. CAHILL ◽  
...  
Keyword(s):  
High Temperature ◽  
Scanning Tunneling Microscopy ◽  
Ostwald Ripening ◽  
Single Atom ◽  
Scanning Tunneling ◽  
Two Dimensional ◽  
Decay Kinetics ◽  
Tunneling Microscopy ◽  
Temperature Scanning

In-situ high-temperature scanning tunneling microscopy was used to follow the coarsening (Ostwald ripening) and decay kinetics of single and multiple two-dimensional TiN islands on atomically flat TiN (001) terraces and in single-atom deep vacancy pits at temperatures of 750–950°C. The rate-limiting mechanism for island decay was found to be surface diffusion rather than adatom attachment/detachment at island edges. We have modeled island-decay kinetics based upon the Gibbs–Thomson and steady state diffusion equations to obtain a step-edge energy per unit length of 0.23±0.05 eV/Å and an activation energy for adatom formation and diffusion of 3.4±0.3 eV.

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