パラジウム上のCO酸化における律速過程の切り替えと脱離ダイナミクスの変化 Switching of the Rate-Limiting Step in CO Oxidation on Palladium and Changes in Product Desorption Dynamics
The working site providing oxygen ad-atoms reactive towards CO was examined on Pd (110) and Pd (100) from the angular and velocity distributions of desorbing CO<SUB>2</SUB>. The distributions were measured with cross correlation time-of-flight techniques. On Pd (110), abrupt changes were found in both the distributions around a critical CO pressure where the rate-limiting step switched over, indicating that CO<SUB>2</SUB> formation sites shifted to O<SUB>2</SUB> dissociation places. On the other hands, no changes were observed on Pd (100), suggesting no shift of CO<SUB>2</SUB> sites with oxygen coverage.
真空 43(3), 337-340, 2000-03-20
The Vacuum Society of Japan