Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Lab Synchrotron Radiat, Beijing 100039, Peoples R China
The ethylene (C2H4) and acetylene (C2H2) co-adsorbed with K on Ru(10(1) over bar 0) surface has been studied by using ultraviolet spectroscopy( UPS). The results show that ethylene (Cz H,) is absorbed in molecular state on Ru(10(1) over bar 0 )surface stably below 200 K. The dehydrogenated of ethylene occurs at 200 K. The main product of the dehydrogenation of the absorbed ethylene (C2H4)is the acetylene (C2H2) After the dehydrogenation of the absorbed ethylene (C2H4), the binding energies of sigma (CC) and sigma (CH) bonds have an increase of 0.2 eV and 0.5 eV respectively. The acetylene is absorbed in molecular state on Ru(10(1) over bar 0 )surface stably at room temperature. On a K pre-covered surface,the sigma (CC) peak disappears at room temperature. The element K promotes the dissociation of acetylene on Ru(10(1) over bar 0 )surface.