Identification of formate from methanol oxidation on Cu(1 0 0) with infrared spectroscopy

Reflection absorption infrared spectroscopy has been used to detect formate (OOCH) following the adsorption of methanol on an oxygen precovered Cu(1 0 0) surface. Formate is identified from a weak peak at 1340 cm−1 due to the symmetric OCO stretch. This assignment is supported by a redshift of the 1340 cm−1 peak to 1317 cm−1 when the surface is precovered with 18O. The amount of formate reaches a maximum for an intermediate oxygen coverage and is undetectable for both low and saturation oxygen coverages.