Surface chemistry is the study of chemical phenomena that occur at the interface of two phases, usually between a gas and a solid or between a liquid and a solid.
One important aspect of surface chemistry studies is to determine whether a molecule attaches itself to a surface by chemisorption or by physisorption. Surface chemistry is of particular importance to the field of heterogeneous catalysis.
The advent of scanning probe microscopies like atomic force microscopy (AFM) and scanning-tunneling microscopy (STM) has stimulated a considerable increase in research activity in surface chemistry. This increase is part of a more general interest in nanotechnology.
Behaviour in solution surface chemistry and colloid chemistry is dependent on the surface charge and the potential distribution in the surrounding electrical double layer.
Irving Langmuir was one of the founders of this field, and a scientific journal on surface chemistry bears his name. The Langmuir adsorption equation is used to model monolayer adsorption where all surface adsorption sites have the same affinity for the adsorbing species.