Measuring membrane permeation rates through the optical visualisation of a single pore

In this work, a dynamic equivalent of a membrane experiment has been produced, by laser-drilling a single pore into a single crystal model membrane. The single pore is then infiltrated with molten carbonate, before being exposed to different gas compositions. Bubbles within the molten carbonate change volume depending on the gas composition, and permeation rates are extracted visually. Overall, this approach allows one to probe vanishingly small driving forces and extract fluxes in regions routine membrane experiments cannot enter.