Triple electrode photogalvanic cell with energy storage capability

DETAILED DESCRIPTION OF THE INVENTION Referring to the figures, and more particularly FIG.
1 thereof, a glass substrate 10 supports a light transparent thin film conductive electrode 12 made from a material such as SnO.
sub.
2.
The combination of the glass and deposited electrode is commercially available and is known as Nesa glass.
A non-conductive substrate 14 is positioned in spaced relationship to the thin film electrode 12 and may be fabricated from a suitable support material such as plastic or glass.
A circumferential wall 16 encloses the interior of the cell, the wall being made from most any suitable inert sealing insulating material such as epoxy.
A thin film electrode 18 is deposited upon the substrate 14 and extends toward the thin film electrode 12.
A layer 20 of charge storing material such as tungsten oxide is deposited as a film upon the electrode 18 by conventional techniques such as evaporation, sputtering or chemical vapor deposition.
The purpose of the layer 20 is to store charge after an irradiating source is removed.
A counterelectrode 22 is also deposited on the substrate 14 in spaced relation to the electrode 18.
The counterelectrode may be made from a suitable material such as carbon or platinized carbon which is deposited by coating or silk screening.
A void created in the interior of the cell is filled with an electrolyte 23 including a suspending agent, such as glycerine, a photoactive material such as TiO.
sub.
2 powder, and a solution of acid, typically sulfuric acid.
This electrolyte was referred to as a charge compensation layer in the previously mentioned copending application.
Preferably, the TiO.
sub.
2 is in the anatase form although the rutile form is satisfactory.
In order to make the electrolyte 23 sensitive to visible light, an agent must be added to the electrolyte.
In a preferred embodiment of the invention, this may be done by incorporating a dye system such as an N-methylphenazine dye system.
Physically, this is accomplished by adding a material such as N-methylphenazine methosulfate which is commercially available from a source such as Eastman Kodak Company, and is available in powdered form