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用XPS和UPS法研究金属Mn、Mg表面与CH_3OH、C_2H_5OH的反应,室温下,ROH(R=CH_3,C_2H_5)以RO~-的形态吸附在Mg表面,Mn表面有较高的活性,ROH除以RO~-的形态被吸附外,部分还分解为O~(2-)和脱附的碳氢化合物,加热至600K时,Mn表面RO~-完全分解为O~(2-)和R,后者与表面氢结合后脱附,部分C_2H_5O~-中的碳成无定形碳并在～675K加氢脱附,ROH在氧化锰表面除以RO~-的形态被吸附外,在高于650K时还产生CH_2O_(a)、C_2H_4O_(a)等,这些物种在700K依然存在,氧化使锰表面断裂R—O和C—C键的活性降低而其脱氢活性仍然存在。
The reaction of metal Mn and Mg with CH_3OH and C_2H_5OH was studied by XPS and UPS. At room temperature, ROH (R = CH_3 and C_2H_5) adsorbed on the surface of Mg with RO ~ -, and had higher activity on the surface of Mn. In the form of RO ~ -, it was also partially decomposed into O ~ (2-) and desorbed hydrocarbons. When heated to 600K, RO ~ - decomposed completely into O ~ (2-) and R ~ The latter is combined with the surface hydrogen and then desorbed. The carbon in some C_2H_5O ~ - is amorphous carbon and is hydrodesorbed at ~ 675K. The ROH is adsorbed on the surface of manganese oxide by RO ~ -, CH_2O_ (a), C_2H_4O_ (a) and so on. These species still exist at 700K, and the activity of R-O and C-C bonds on the surface of manganese decreases due to oxidation, and the dehydrogenation activity still exists.