Direct Determination of the Mass of an Underpotentially Deposited Monolayer of Lead on Gold

The mass of an underpotentially deposited monolayer of lead on gold has been measured in situ by using a quartz crystal microbalance. The mass of the monolayer calculated from first principles using the frequency change of the microbalance corresponds to a coverage of 1.3 × 10–9 mol/cm3. As determined in the present study, at complete coverage, the electrosorption valency for lead deposition onto gold is 2.08 ± 0.10, which is in good agreement with literature values. © 1986, American Chemical Society. All rights reserved.