Peter G. P. Ang

Photoelectrochemical Investigation of a Poly(Ethylene Oxide) Cell

The photoelectrochemical properties of cells based on the solid polymer electrolyte (SPE) poly(ethylene oxide)/NaSCN with Na2S/S as a redox species are investigated experimentally. The preparation of the SPE is described in detail. Current/voltage curves or voltage/time are shown for cells using p-InP/SPE/conducting-glass, n-GaAs/SPE/conducting-glass, and p-InP/SPE/n-CdS structures. It is concluded that practical cells based on SPE of this type will require increases in the ionic conductivity of poly(ethylene oxide). 13 references.

Photoelectrochemical systems with energy storage

Photoelectrochemical cells having the capability of energy storage are covered. Photoanodes used for these cells were selected from MoSe2, GaAs and CdSe. Redox electrolyte species present at the semiconductor–electrolyte interface included Br–/Br2(MoSe2), S2–/S2–n(CdSe) and Se2–/Se2–2(GaAs). Electroactive materials at the counter-electrode of the storage systems were I–I2, Se2–/Se2–2 and Cd.The performance of these photoelectrochemical storage cells for charge upon photoanode illumination and their subsequent electrochemical discharge is discussed.

Surface‐Modified p ‐ InP Photocathodes in Sulfide/Polysulfide Electrolyte

A chemical procedure is reported to modify the semiconductor surface which results in an efficient p-InP/S/sup 2-/,Sx/sup 2-/ photoelectrochemical cell. The procedure is as follows: The p-InP electrode was initially etched in 12M HCl for 1-2 minutes, followed by immersion in polysulfide solution (1M Na/sub 2/S+1M/sub 2/S or 2.5M Na/sub 2/s+1M S+1M NaOH. To the polysulfide-wetted surface of the p-InP, a drop of 0.2M CoCl/sub 2/ was added. A black precipitate of cobalt sulfide was immediately formed, the majority of which was rinsed off with deionized water. 7 refs.