Observation of concentration gradients by the laser beam deflection sensor

High-resolution spatially resolved visible absorption spectrometry of the electrochemical diffusion layer

“…Although the optical arrangement had a theoretical resolution of 4 pm, the 60-80-pm correction for beam displacement and the diffraction along the electrode will lead to much poorer actual resolution, and a resolution test was not discussed. Another absorption technique is based on deflection of a probe beam caused by a thermal gradient produced when a pump beam is absorbed by electrogenerated material (33). As with other focused-beam techniques, the resolution is limited to the beam waist of 25-50 pm.…”

Application of photothermal deflection spectroscopy to electrochemical interfaces

“…This is called selective measurement of concentration gradients. Pawliszyn, et al have demonstrated that the AC signal at o· can be used to measure the concentration gradient of a single electrolyte species and can measure the absorption spectrum of the species [25].…”

“…By choosing excitation wavelength, the concentration gradient of specific species can be ''illuminated" to produces a thermal gradient proportional to the concentration gradient of only that species. This type of measurement is not generally applicable, but is very useful when possible [25].…”

Optical beam deflection approach for studying ion-exchange reactions occurring at a single ion-exchange resin particle

“…On the other hand, the OBD method has also been applied for exploring a concentration gradient [15][16][17][18][19] in chemical and electrochemical systems. The OBD method also can be used for exploring a concentration gradient in flow systems [20][21][22].…”