Abstract: An optically transparent platinium minigrid thin-layer spectroelectrochemical cell (OTTLSEC) with two platinium plates at each side of working electrode(WE) as auxiliary electrodes was designed and constructed. The WE, AE and two quartz plates form a "sandwich" with teflon film as the eliminator for minimizing the edge diffusional effect, A small inner channel sets an internal reference point for accurate potential control. Symmetrical thin-layer cyclic voltammograms with negligible peak-to-peak separation were obtained by this cell for ferri/ferrocyanide couple at low scan rates. The excellent optical and electrochemical responses of this couple in the cell by cyclic voltammetry, cyclic voltaabsorptometry, constant potential control in situ spectrum, double potential step-chronoabsorptometry and double potential step-chronocoulometry were achieved.

Key words: spectroelectrochemistry, thin-layer cell, platinium minigrid electrode, ferricyanide