A comparative study of surface energy data from atomic force microscopy and from contact angle goniometry

Forces of adhesion have been measured for interactions involving self-assembled monolayers or polymer-film structures that had each been deposited onto a gold-coated glass substrate and a probing, gold-coated cantilever. The data have been fitted into mathematical models that allow the calculation of surface energy by considering the work done for the separation of the identically coated contacting surfaces. These values of surface energy are in close agreement with those from corresponding contact angle determinations, highlighting the potential usefulness of the technique for the study of surfaces at a resolution level approaching 1000 atoms. Comparative studies show that the employment of the atomic force microscopy technique may be preferable for the study of samples that are susceptible to penetration by liquids or for investigations under conditions that exceed the useful limits of conventional probing techniques involving liquids.