The reaction of formic acid with pre-oxidised Cu(110) surfaces is re-e
valuated on the basis of new temperature programmed desorption and X-r
ay photoelectron spectroscopy results. IT is shown that at high oxygen
coverages and for high formic acid exposures, or after co-adsorption
of formic acid and dioxygen, a surface carbonate is formed. The carbon
ate appears to be very similar to that formed by the oxidation of CO2,
at higher pressures, which was reported in an earlier paper. The resu
lts also account for a number of unexplained observations on this syst
em and provide further support for the involvement of carbonate in met
hanol synthesis on copper. (C) 1998 Elsevier Science B.V. All rights r
eserved.