科研之友
微信
新浪微博
Facebook
分享链接
摘要
The adsorption and dissociation of ammonia on Ru(0001) was studied by scanning tunneling microscopy (STM), density functional theory (DFT), and STM contrast simulations. Various NHx (with x = 0-2) species were formed by controlled STM tip manipulation. Each species shows a characteristic imaging contrast in STM measurements, changing from a protrusion for NH3 and NH2, to a depression for NH and N. The adsorption sites of each species determined from the STM images and their contrast agree well with DFT calculations and STM image simulations. Ammonia was found to interact with hydrogen atoms present on the surface, leading to the formation of triangular-shaped NH3 + 3H complexes. At submonolayer coverage, ammonia dimers were also identified and their formation and dissociation were observed upon tip manipulation.
- 出版日期2012-12-6
