Recent advances in resolving kinetic and dynamic processes at the air/water interface using specular neutron reflectometry

This review addresses significant recent advances in kinetic and dynamic studies at the air/water interface using specular neutron reflectometry. A step change in the capabilities to resolve these processes in systems related to soft matter, biophysics, environment and health has been delivered primarily by the FIGARO instrument at the Institut Laue-Langevin. It is now routinely carried out to resolve the surface excess of single-component, deuterated monolayers on the second time scale and the interfacial composition of binary mixtures where only one component is deuterated on the minute time scale. This resource has been exploited extensively in the last few years to provide new insight into the kinetics of oxidation of monolayers targeted from the gas phase and the adsorption of various types of molecules from solution as well as the dynamic molecular interactions of systems under continuous flow and during repeated compression/expansion cycles of a Langmuir trough. A perspective is given on current capabilities and future developments that will result from further developments in instrumentation and sample environment.