The possibility of single C–H bond activation in CH4 on a MoO3-supported Pt catalyst: A density functional theory study

Abstract

Methane activation is a crucial step in the conversion of methane to valuable oxygenated products. In heterogeneous catalysis, however, methane activation often leads to complete dissociation: If a catalyst can activate the first C–H bond in ${\mathrm{CH}}_{\mathrm{4}},$ it can often break the remaining C–H bonds. In this study, using density functional theory, we illustrate that single C–H bond activation in ${\mathrm{CH}}_{\mathrm{4}}$ is possible. We choose a model system which consists of isolated Pt atoms on a ${\mathrm{MoO}}_{\mathrm{3}}\text{(010)}$ surface. We find that the Pt atoms on this surface can readily activate the first C–H bond in methane. The reaction barrier of only 0.3 eV obtained in this study is significantly lower than that on a Pt(111) surface. We also find, in contrast to the processes on pure metal surfaces, that the further dehydrogenation of methyl $({\mathrm{CH}}_{\mathrm{3}})$ is very energetically unfavorable on the ${\mathrm{MoO}}_{\mathrm{3}}$ -supported Pt catalyst.