• 文献标题:   Reaction Mechanism of Methanol to Formaldehyde over Fe- and FeO-Modified Graphene
  • 文献类型:   Article
  • 作  者:   THIVASASITH A, SIRIJARAENSRE J, KHONGPRACHA P, WARAKULWIT C, JANSANG B, LIMTRAKUL J
  • 作者关键词:   density functional calculation, graphene, iron, methanol, oxidation
  • 出版物名称:   CHEMPHYSCHEM
  • ISSN:   1439-4235 EI 1439-7641
  • 通讯作者地址:   Kasetsart Univ
  • 被引频次:   11
  • DOI:   10.1002/cphc.201402702
  • 出版年:   2015

▎ 摘  要

We employed periodic DFT calculations (PBE-D2) to investigate the catalytic conversion of methanol over graphene embedded with Fe and FeO. Two possible pathways of dehydrogenation to formaldehyde and dehydration to dimethyl ether (DME) over these catalysts were examined. Both processes are initiated with the activation of methanol over the catalytic center through OH cleavage. As a result, a methoxo-containing intermediate is formed. Subsequently, H-transfer from the methoxy to the adjacent ligand leads to the formation of formaldehyde. Conversely, the activation of the second methanol over the intermediate gives DME and H2O. Over Fe/graphene, the dehydration process is kinetically and thermodynamically preferable. Unlike Fe/graphene, FeO/graphene is predicted to be an efficient catalyst for the dehydrogenation process. Oxidative dehydrogenation over FeO/graphene takes place through two steps with free energy barriers of 5.7 and 10.2 kcalmol(-1).