Photothermal spectrometry for membrane and interfacial region studies†

In this paper the application of photothermal techniques to membrane and interfacial studies is described. Thus the techniques of photothermal and concentration gradient induced beam deflection, photoacoustic spectrometry and thermal lens spectrometry are described as applied to the study of thin films, skin and diffusion through membranes. Techniques for the measurement of thermal diffusivity in thin polymer films and skin are also described. Their theoretical basis for application is discussed together with the limitations of each technique. Finally the future development of photothermal techniques for these applications is assessed.