Cuprous Oxide Solar Cell
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Overview
When copper metal is oxidized it can take several oxidation states.
Cupric oxide with a copper(II) oxidation state is black: 2 Cu + O2 → 2 CuO
cuprous oxide is with the copper(I) oxidation state is red.
- 4 Cu + O2 → 2 Cu2O.
Cuprous oxide is a semiconductor. It has a bandgap between it ground state and its conduction band. Without light some electrons are able to jump the band and it acts as a battery. With light the cuprous oxide jumps to the conduction band and increased electricity flows. In this design the charge moves through a gelatin electroylte and to a non oxidized collection electrode. Using a gelatin electrolyte is less messy that a purely liquid electrolyte. A solid clear conductor is not great for this application because it can not make uniform contact with the copper surface.
Materials
- Copper foil (snail tape) from the gardening store
- Wires and solder
- Clear rigid plastic sheet (old cd case, or plastic lid from salad container.)
- clear plastic packing tape
- clear gelatin
- table salt
- volt meter