The mercury monolayer carbon fiber electrode (MMCFE) represents a low-dimensional system [1] characterized by quantization of the electronic states providing novel physical and chemical properties cardinally different compared to the ordinary bulk systems – either the mercury thick film electrode or the bare carbon fiber one.
Indeed, the extraordinarily high voltammetric sensitivity (of the femtomolar order) of MMCFE [2], [3], [4] and [5] for a time scale ⩽1 s should be certainly attributed to the low-dimensionality of this electrode.
Despite the fact that the catalytic regeneration of metal atoms (Pb and Cu alone [2] and [3] or in Cu2+ complexes [4] and [5]) during the positive-going semi-cycle under action of the atomic hydrogen (H0) (Reaction (1)) verifies an explanation of high and unusual sensitivity,