Surface energy analysis
The surface energy of solid is analogous to the surface tension of a liquid. For solid to exist, it must be energetically favorable (of lower energy) for its molecules to form bonds with each other. It follows that the molecules at the solid's surface are in the less favorable state (at higher energy), as they are not surrounded by other bulk molecules. I use inverse gas chromatography to measure the surface energy components of porous materials and working to establish a relationship with the adsorption process.