洪偉修Hung, Wei-Hsiu鄭智文Jheng, Jhih-Wun2019-09-042019-7-92019-09-042014http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22GN060142057S%22.&%22.id.&http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/100444利用程溫脫附質譜(TPD)量測脫附碎片，並以X光光電子能譜(XPS)作為輔助，研究巰基(SH)與羥基(OH)不同取代基於苯環上，並比較苯硫酚與苯酚其吸附及熱分解之反應機構。 苯硫酚於低溫105 K曝露於Ge(100)上，會以斷硫氫鍵鍵結於表面上，在低曝露量下， C6H5S上的苯環以平躺的方式吸附於表面上，於高曝露量時，C6H5S上的苯環以站立的方式吸附於表面，達高曝露量時，出現未分解的化學吸附態與多層覆蓋的物理吸附。 苯硫酚於升溫脫附過程中，C6H5SH、H2、GeS、H2S、C6H6為主要分解產物，575 K時有苯硫酚重組合脫附峰出現，苯環的生成為C6H5S斷碳硫鍵鍵結於表面上，而苯環有兩種不同吸附態，於程溫脫附質譜中看到，表面的氫原子會與自己重組合脫附，或與硫生成H2S脫附。而高溫時產生的硫化鍺以斷Ge-Ge的方式生成。 苯酚吸附與苯硫酚大致相同，但熱分解形式不同，因碳氧鍵穩定不易斷鍵，故熱分解路徑不同，根據文獻所示，氧化鍺與硫化鍺所產生機制相同，應於同一溫度出現，但氧化鍺出現的溫度比文獻所提還高，是因氧化鍺的生成需待碳氧鍵的斷裂。另外，在程溫脫附儀訊號上可看到三次苯酚重組合訊號，我們利用理論計算出的位能配合所做實驗數據共同解釋。The adsorption and thermal reactions of thiophenol (C6H5SH) and phenol (C6H5OH) on Ge(100) surface were studied with temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) using synchrotron radiation. The desorbed products of thermal reactions could be measured by TPD, and the XPS was utilized to identify the surface species. Most of the thiophenol adsorbed on Ge(100) at 105 K dissociated into surface C6H5S(a) and H(a). The thiophenoxy group lay flat in the low-exposure regime and stood upright upon higher exposures. The chemsorbed and physorbed thiophenol appeared on the Ge(100) at larger exposures. The desorption products of C6H5SH were C6H5SH(g), H2(g), GeS(g), H2S(g), and C6H6(g). At 575K, the desorption of thiophenol resulted from the recombination of C6H5S(ad) and H(ad). The surface C6H5S(a) cleaved the carbon-sulfur bond to release the C6H5 bond and reacted with H to desorb benzene. According to the TPD spectra, we propose that benzene has two adsorption states. The desorption of hydrogen with recombination of H(ad) + H(ad) and some hydrogen reacted with surface S to become H2S(g).At 690K, GeS(g) desorbed from the surface due to the cleavage of the Ge-Ge bond. The adsorption features of phenol and thiophenol are almost the same, but the thermal decomposition reactions are different because the carbon-oxygen bond is stable. Phenoxy group cleaves the carbon-oxide bond to produce GeO(g) at higher temperature in the TPD spectra. Three desorption peaks in TPD spectra are observed due to recombination reactions. According to the experimental data and computational result, we propose the reactions mechanisms of C6H5SH and C6H5OH thermal reaction on Ge(100).Ge(100)苯硫酚苯酚Ge(100)thiophenolphenol