CHEMICALLY DERIVATIZED SEMICONDUCTOR PHOTOELECTRODES - A TECHNIQUE FOR THE STABILIZATION OF n-TYPE SEMICONDUCTORS.

Pretreated Au, Pt, n-type Si, and n-type Ge can be derivatized with trichlorosilylferrocene, (1,1 prime -ferrocenediyl)dichlorosilane, and 1,1 prime -bis(triethoxysilyl)ferrocene to yield electroactive, surface-attached, oligomeric ferrocene material. Derivatized, n-type semiconductors exhibit photoeffects expected for such an electrode material; irradiated derivatized n-type Si can be used to effect the oxidation of solution reductants by mediated electron transfer, unique proof for which comes from the semiconductor electrode that responds to two stimuli, light and potential. The sustained, mediated oxidation of Fe(CN)//6**4** minus in aqueous solution in an uphill sense by irradiation of derivatized n-type Si is possible whereas a naked n-type Si undergoes decomposition to SiO//x at a rate too fast to allow sustained energy conversion. This establishes the principle of manipulating interfacial charge-transfer kinetics for practical applications.