Experimental aspects of use of the quartz crystal microbalance in solution

TTL-based circuitry is described for measuring the resonant frequency of an oscillating quartz crystal having one face in contact with an electrolytic solution. The circuitry facilitates application of the quartz crystal microbalance technique to in situ electrogravimetric studies of submonolayer and many monolayer thick electrodeposited and electrosorbed films. The effect of solution temperature and viscosity, and height of liquid above the crystal were investigated and the results correlated with theory. An in situ solution method for determining the mass sensitivity of the crystal is described and the latter sensitivity is shown to be the same as the calculated vacuum sensitivity. The effect of double layer structure and specific adsorption is discussed.