| Summary: | 碩士 === 國立成功大學 === 化學系碩博士班 === 98 === Temperature-programmed reaction/desorption (TPR/D) and reflection absorption infrared spectroscopy (RAIRS) have been employed to investigate the thermal reactions and surface intermediates of ClCH2CH2CH2OH on clean and oxygen-precovered Ni(111) in an ultra-high vacuum system. On Ni(111), -OCH2CH2CH2Cl and -CH2CH2CH2OH surface intermediates are formed from the scission of O-H and C-Cl bonds of ClCH2CH2CH2OH below 197 K, but some ClCH2CH2CH2OH dehydrated to form ClCH2CHCH2 below 200 K instead of breaking O-H or C-Cl bonds. 3-Hydroxypropyl intermediate decomposed and evolved into C2H4, CH3OH, and CO via complex reactions between 150 and 220 K. On the other hand, 3-Chloropropoxide intermediate continually decomposed between 230 and 300 K and dissociated completely above 300 K. No other product was found except for H2 and CO above 300 K. On oxygen-precovered Ni(111), TPR/D and IR experiment results at lower exposure(≦0.48 ML) are similar to ClCH2CH2CH2OH/Ni(111) case. However, we discovered that CH3CHCH2 and CH3CH2CHO evolved at 178 K and 346 K respectively between 0.6~1 ML on oxygen-precovered Ni(111). CH3CH2CHO may formed from oxametallacycle(-CH2CH2CH2O-) intermediate generated around 300 K by RAIRS studies.
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