Abstract Electrochemistry of bilayer electrodes has until now been investigated mainly in the dark. For the further development of the photoelectrochemistry of bilayer electrodes and its application to optical-energy storage, a polymer of N-[4-[2-(trimethoxysilyl)ethyl]benzyl]-N′-methyl-4,4′-bipyridinium dibromide (BVSiBr2), a photoredox siloxane polymer, was employed as a photosensitive outer-layer, and bis(2,2′-bipyridine)bis(4-vinylpyridine)ruthenium(II) bis(hexafluorophosphate), [Ru(bpy)2(vpy)2](PF6)2, or tris(4-methyl-4′-viny-2,2′-bipyridine)iron(II) bis(hexafluorophosphate), [Fe(vbpy)3](PF6)2 was electrochemically polymerized as the inner layer on the surface of an SnO2 electrode. Direct and indirect photochemical reductions(trapping) of the outer layer siloxan polymer were attempted in the following ways: 1) the outer-layer, poly(BVSiBr2), was chemically trapped with a methylviologen radical, MV\underset.+, produced photochemically in an illumination cell and transferred to the electrochemical cell, 2) the outer-layer was photochemically trapped by UV irradiation in the presence of photosensitive alcohols (i-PrOH and EtOH) and 3) by photochemical trapping with tris(2,2′-bipyridine)ruthenium and triethanolamine. The 1st and the 2nd methods yielded results expressed by cyclic voltammograms showing an accumulation of poly(BVSi\underset.+), that is, a storage of optical energy in the outer-layer. The result of the 3rd method was negative.