In situ study of selective oxidation of methanol to formaldehyde over copper

Selective methanol oxidation to formaldehyde over polycrystalline copper has been studied with the use of in situ XPS combined with mass spectrometry. It has been shown that the copper surface completely covered by methoxy groups exhibits low activity in methanol oxidation, whereas the metallic copper with sub-oxide oxygen is active in the selective oxidation of methanol to formaldehyde. The concentration of the sub-oxide oxygen species seems to correlate with the rate of formaldehyde production.