Abstract: The transient ring currents of the RRDE n-InP semiconductor disk-gold ring irradiated with a light step from dark to 25 mW·cm~(-2) with the seven different rota-tion speeds between 590 and 7000 r. p. m. in 0.101 mol·L~(-1) K_4 Fe(CN)_6 have been studied Experimental data were fitted by the computer. The diffusion coefficient of [Fe(CN)_6]~(3-) ion found is D=3.3×10~(-6) em~2·s~(-1) and the theoratical collection efficiency calculated for thin-gap and thin-ring RRDE is N=0.20 these are in good agreement with the literature. The experimental value of ωτ_0 agree with the theoratical value.
The agreement between the experiment and the theory suggests that the electrode reaction on n-InP is a simple photoelectro-chemical reaction, i.e.
[Fe(CN)_6]~(4-)+h~+→[Fe(CO)_6]~(3-).