著者

北田 暁彦 平島 秀水 小川 淳也 中野 美尚 松本 健俊 中村 潤児

出版者

公益社団法人 日本表面科学会

雑誌

表面科学 = Journal of The Surface Science Society of Japan (ISSN:03885321)

巻号頁・発行日

vol.25, no.9, pp.580-585, 2004-09-10

参考文献数

18

---

The effect of step-edges on the dissociative adsorption of H<Sub>2</Sub>S has been studied on a Ni(111) surface using scanning tunneling microscopy (STM), Auger electron spectroscopy (AES) and low energy electron diffraction (LEED). Exposure of Ni(111) to H<Sub>2</Sub>S at room temperature results in the formation of S islands with the structures of p(2&times;2) and reconstructed c(5&radic;3&times;9) rect in the vicinity of step-edges. Subsequently, H<Sub>2</Sub>S dissociates on the terrace of Ni(111), leading to the formation of unique S species with a string structure. The STM observation indicates that the dissociation of H<Sub>2</Sub>S takes place on both step-edges and terraces. The dissociative adsorption of CO as well as formation of carbide islands also take place preferentially at the step-edges. It is thus suggested that a small amount of sulfur located at step-edges effectively deactivate CO dissociation in the methanation reaction.