Investigations on adsorption kinetics of sodium decyl sulphate at the mercury/electrolyte interface

Adsorption of sodium dodecyl sulfate on the bismuth (111), (001) and planes

“…1)) and the imaginary component Z 00 is equal to 1/jC s x with j ¼ ffiffiffiffiffiffi ffi À1 p , C s is series capacitance ie. C s = f(x) corresponds to the total capacitance of experimental series R, C-circuit where x is an angular frequency [29][30][31][32][33][34][35][36][37][38][39][40]. The non-linear least square fitting data [38,39] show that Z 00 , Z 0 -curves for the Bijbase electrolyte interface can be simulated by the equivalent circuit (inset in Fig.…”

“…On the other hand, R ad in parallel to the double layer capacitance can also be traced back to a slow 'true' heterogeneous charge transfer process (H + (H 2 O) n + e À ! H ads + nH 2 O) not related to the adsorption-desorption process of the electrolyte ions [29][30][31][32][33][34][38][39][40][41][42][43][44][45]. However, the very low values of current density, j, and the very weak dependence of j on electrode potential, as well as very high R ad indicate the absence of quick 'true' faradaic reactions on the Bi single crystal planejbase electrolyte interface [1][2][3][4][5][6]42,43] at À0.4 V < E < À1.6 V (AgjAgCl).…”

“…At potentials more negative than the adsorptiondesorption peak potential E peak , the Z 00 , Z 0 plots can be represented by very well depressed semi-circles with experimental relaxation time s m = (x m ) À1 = (2pf) À1 , which corresponds to mixed kinetics (i.e. the SDS adsorption process is limited by the slow adsorption (s K ) and diffusion (s D ) steps) [1][2][3][4][5][6]21,22,[29][30][31][32][33][34][35][36][37] (Figs. 2 and 3b).…”

“…Experimental impedance data were mainly fitted using the equivalent circuits (EC) based on various theoretical models [29][30][31][32][33][34][35][36][37] and illustrated in Fig. 7.…”

“…Frumkin and Melik-Gaikazyan first observed the frequency-dependence of impedance for a Hg electrode adsorbing the neutral organic molecules [21,22] and the detailed analysis of physical models and theoretical background is given in previous papers [1][2][3][4][5][6]23,[29][30][31][32][33][34][35][36][37].…”