ADSORPTION OF WATER ON COPPER AND CUPROUS-OXIDE

Water adsorption and desorption are presented for evaporated Cu and Cu//2O using a quartz crystal oscillator method with an ultimate sensitivity of 10** minus **8 gcm** minus **2. Cu//2O adsorbs more water than Cu at a given relative humidity (RH). Higher adsorbed water content on Cu//2O at a given RH partly accounts for the breakdown of its passivity against sulfidation at elevated RH as reported earlier by the author. Isotherms are fitted to a BET-type (type II) model. From the BET parameters, the monolayer capacity and the heat of adsorption have been determined. These results are relevant to copper corrosion.