Alloy catalyst in a reactive environment: the example of ag-cu particles for ethylene epoxidation.
نویسندگان
چکیده
Combining first-principles calculations and in situ photoelectron spectroscopy, we show how the composition and structure of the surface of an alloy catalyst is affected by the temperature and pressure of the reagents. The Ag-Cu alloy, recently proposed as an improved catalyst for ethylene epoxidation, forms a thin Cu-O surface oxide, while a Ag-Cu surface alloy is found not to be stable. Several possible surface structures are identified, among which the catalyst surface is likely to dynamically evolve under reaction conditions.
منابع مشابه
First-principles study of the mechanism of ethylene epoxidation over Ag–Cu particles†
Silver–copper alloys have been proposed as catalysts for ethylene epoxidation due to their superior selectivity compared to pure silver, the predominant catalyst for this reaction. Under reaction conditions it has been previously shown that, rather than a two-dimensional (2D) Ag–Cu alloy, a thin copper oxide-like layer forms on top of silver, and several possible surface structures were identif...
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ورودعنوان ژورنال:
- Physical review letters
دوره 104 3 شماره
صفحات -
تاریخ انتشار 2010