Elucidating interactions of the epoxide ring on Pt(111) by comparing reaction pathways of propylene oxide and 1-epoxy-3-butene

Propylene oxide (PO) and 1-epoxy-3-butene (EpB) were used as probe molecules to study the interaction between the epoxide ring and the Pt(111) surface with temperature programmed desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS). The effect of the C=C bond on the adsorption and reaction of the epoxide was investigated by comparing PO and EpB. For both molecules, the pathways of deoxygenation and decomposition were observed in TPD with EpB being more reactive than PO on Pt(111) due to the presence of the C=C bond. This was supported by HREELS measurements, which indicated strong interactions between the C=C bond and the Pt(111) surface, with the decomposition of EpB happening more readily at relatively low temperatures. In addition, PO and EpB were found to be less reactive on oxygen-modified Pt(111) than on clean Pt(111). These results provide insight into the reactivity of PO and EpB on Pt(111), including how the presence of the C=C bond and the modification with surface oxygen affect the interaction of the epoxide ring with the Pt(111) surface.