SCANNING TUNNELING MICROSCOPY CHARACTERIZATION OF AMMONIA-SYNTHESIS CATALYSTS

被引:11
作者
BESENBACHER, F [1 ]
LAEGSAARD, E [1 ]
STENSGAARD, I [1 ]
STOLTZE, P [1 ]
TOPSOE, H [1 ]
机构
[1] HALDOR RES LABS TOPSOE,DK-2800 LYNGBY,DENMARK
关键词
SCANNING TUNNELING MICROSCOPY (STM); AMMONIA SYNTHESIS CATALYSTS; SURFACE CHEMISTRY;
D O I
10.1007/BF00764189
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The possibility of studying the texture of catalysts at the atomic level by Scanning Tunneling Microscopy (STM) is demonstrated. It is shown that high resolution pictures can be obtained even for a passivated ammonia synthesis catalyst using a scanning tunneling microscope operating in air. The STM results reveal that the catalyst has a spongy pore structure with both hole and slit shaped pores. The catalyst surfaces are observed to contain fine quite regular ridge structures with a direction that tentatively is related to the (110) direction of iron. The presence of the ridge structures is apparently the result of the topotactic nature of the reduction process and a preference to expose (111) Fe facets.
引用
收藏
页码:273 / 282
页数:10
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