Abstract
Using the differential capacitance technique, the flat-band potential of n-type TiO2, SnO2, SrTiO3, KTaO3, and KTa0.77Nb0.23O3 electrodes has been determined as a function of pH in aqueous electrolytes. Plots of flat-band potential vs. pH are linear in all cases and have a slope of ∼0.059 V/pH unit. The flat-band potential correlates nicely with the onset for photoanodic currents corresponding to O2 evolution at the n-type semiconductor and H2 at the dark Pt cathode. The ordering of flat-band potentials at a given pH is SrTiO3 ∼ KTaO3 ∼ KTa0.77Nb0.23O3 > TiO2 > SnO2 (SnO2 most positive vs. SCE).
| Original language | English |
|---|---|
| Pages (from-to) | 2641-2645 |
| Number of pages | 5 |
| Journal | Journal of Physical Chemistry |
| Volume | 80 |
| Issue number | 24 |
| DOIs | |
| State | Published - 1976 |