Patent ID: 8193443

Claim:
A photovoltaic cell comprising: a first substrate and a first electrode on said first substrate, or, alternatively, a first metal foil acting as a first substrate and a first electrode, a porous semiconductor layer which is a photoactive layer, on said first electrode, a porous spacer layer on said porous semiconductor layer, a second electrode as counter-electrode on said porous spacer layer and in physical contact therewith, said second electrode being in the form of a layer covering said porous spacer layer, a second substrate on said second electrode, wherein said porous semiconductor layer has a first interstitial space formed by pores of said porous semiconductor layer, and said porous spacer layer has a second interstitial space formed by pores of said porous spacer layer, wherein said first interstitial space and said second interstitial space are in fluid connection with each other and are filled with an electrolyte, and wherein said porous spacer layer on one side is in physical contact with said second electrode, and wherein said porous spacer layer on another side is in physical contact with said porous semiconductor layer, wherein said porous spacer layer is made of particles having sizes in the range of from 1 nm to 500 nm, wherein said porous spacer layer has a thickness in the range of from 1 μm to 10 μm, and wherein said porous spacer layer is a layer formed by stacking up spacer particles on each other.