One of the great challenges in heterogeneous catalysis is to convert the row materials, such as methane, carbon dioxide and also ethanol into more valuable compounds. Noble metals are active catalysts for the activation of these molecules, but due their high price and rapid deactivation the synthesis and search for new effective catalysts is really needed. One of the candidates is Mo2C, which exhibits favorable catalytic bahavior. Its combination with ZSM-5 exhibited a unique catalytic performance in the direct conversion of methane and other alkanes into benzene [1]. It also proved to be an excellent catalyst for the aromatization of ethanol [2]. The reaction pathway of ethanol on Mo2C, however, can be dramatically altered by changing the support. Mo2C prepared by the reaction of MoO3 with multiwall carbon nanotube of high surface area resulted in an active catalyst for the production of H2 instead of the aromatization reaction [3]. In order to obtain a deeper insight into these processes parallel with the catalytic studies we examained thoroughly the reaction pathways of the primary products (various CHx fragmnets, and CHxO species ) formed on Mo2C in the activation of hydrocarbons and ethanol by means of various electron spectroscopic methods (FTIR, RIAS, XPS, UPS, HREELS, STM etc.).
The presentation consists of following parts: (i) summarization of the recent results obtained on the chemistry of various CHx fragments on Mo2C/Mo(100), (ii) an account on the interaction of ethanol with pure and potassium-promoted Mo2C/Mo(100), (iii) XPS study on the formation of Mo2C in the reaction of MoO3 with carbon in the flow of hydrogen, and (iv) catalytic performance of Mo2C prepared on carbon in the decomposition of ethanol to produce hydrogen.
References:
[1] A. Széchenyi, F. Solymosi App. Catal. A Gen. 306 (2006) 149 and references therein
[2] R. Barthos, A. Széchenyi, F. Solymosi J. Phys Chem B 110 (2006) 21816.
[3] A Széchenyi, R. Barthos, F. Solymosi Cat. Lett. in press.
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