“…impedance spectroscopy (IS), 12,13 solid-state NMR techniques, 14,15 pulsed field gradient NMR (PFG-NMR) 16,17 and tracer diffusion (RTD). [18][19][20][21] IS is one of the most commonly used techniques, however, the technique relies on a well-defined electrical contact between the samples and two electrodes. One can envisage situations where a sample contact with two electrodes is not possible or not desirable.…”