C-O BOND SCISSION DURING METHANOL DECOMPOSITION ON (1X1)PT(110)

Recently there has been some controversy whether C-O bond scission occurs during methanol decomposition on the (111) faces of platinum and palladium. Here, the decomposition of methanol on Pt(110) is examined by TPD and EELS. It is found that, on the (1 X 1) reconstruction of Pt(110), the methanol adsorbs molecularly 100 K. When the layer is heated to 140 K, the C-O bond breaks to yield water and a mixture of CH(x ad) species. The CH(x ad) species then further react to form CH4, H(ad), C(ad), and some as yet unidentified higher hydrocarbons. By comparison, if the sample preparation procedure is changed to produce a (2 x 1) reconstruction no water, methane, carbon, or higher hydrocarbons are detected. These results demonstrate that C-0 bond scission can occur during methanol decomposition on platinum. However, the extent of bond scission is strongly affected by small changes in the sample preparation procedures and surface structure of the sample. This may explain why the previous observations of C-O bond scission from some laboratories were not reproduced in other laboratories.