Iron Oxide Semiconductor Electrodes in Photoassisted Electrolysis of Water

Abstract

The preparation of polycrystalline n-type iron oxide electrodes by heating of iron samples in air is reported. The behavior of these electrodes in aqueous solutions of different pH values in the presence and absence of illumination is shown. The photocurrent response of these electrodes to all wavelengths in the visible region is seen. Photoassisted electrolysis of water occurs at these wavelengths resulting in the evolution of oxygen bubbles at the iron oxide electrodes with no noticeable corrosion problems in pH 4.0 acetate buffer to 5.5M KOH solutions * Electrochemical Society Student Member. ? Electrochemical Society Honorary :Member.

Preparation and properties of substituted iron tungstates

“…The nature of the variation of resistivity with 1 x of FeiNrxWO 4 suggests that interchain electron transfer may occur in this structure.…”

“…Although the phase boundary between a-Fe203 and Fe304 is sharp (7), a-Fe203 can be made conducting by the introduction of small amounts of Fe304 by exposure to a reducing atmosphere. The spinel Fe 0 4 contains both iron(II) and iron (III) on octahedral sites, and conduction occurs via electron transfer from iron (II) to iron(III). However, iron(III) oxide itself crystallizes with the corundum structure, which contains only trivalent iron, and cannot tolerate deviations from a metal-to-oxygen ratio of 2:3.…”

Cooperative Dynamics of Coupled and Forced Oscillators

“…Experiments showed that the local perturbation of this excitable system with laser beam causes a front of activation that spreads over the entire electrode which after that gradually returns to the passive state. The effect of laser beam, dissolving locally the passive layer, is explained in terms of the n-type semiconducting properties of the oxide film [91,92]. It is thus clear that if the Fe/H 2 SO 4 system oscillates spontaneously between the passive and the active state of the iron electrode, the laser beam can affect its dynamics only if it is applied while the system is in a passive state.…”

Photoelectronic Properties of Ternary Niobium Oxides

“…Unfortunately, any attempt to reduce ferric oxide results-in the formation of magnetite as a distinct separate phase, and there is no solubility of this spinel in the corundum structure (5, 6). Thus, all the properties reported above for Fe 2 0 3 were measured either on multiphase samples or on samples which contained impurities.…”

“…Nevertheless, the non-active A-site ions in such ternary compounds as BaTiO 3 Cl .0 -2-(4, 7, 9, 0). Consequently, it multiple photoactive centers can maintain sufficiently independent existence in a single compound, it would be conceivable that significant deviations from the usual correlation of high flat-band potentials with low band-gap energies might occur.…”