Photoactive Devices and Components with Enhanced Efficiency
Devices, compositions and methods for producing photoactive devices, systems and compositions that have improved conversion efficiencies relative to previously described devices, systems and compositions. This improved efficiency is generally obtained by one or both of improving the efficiency of light absorption into the photoactive component, and improving the efficiency of energy extraction from that active component.
1 . A photoactive device, comprising:
at least first and second discrete photoactive layers sandwiched between a first electrode layer and a second electrode layer;
at least a first transparent boundary layer separating the first photoactive layer from the second photoactive layer, the boundary layer being substantially discrete from each of the first and second photoactive layers.
2 . The photoactive device of claim 1 , wherein the boundary layer comprises second and third electrode layers insulated from each other, the third electrode layer electrically contacting the first photoactive layer and the fourth electrode layer electrically contacting the second photoactive layer.
3 . The photoactive device of claim 1 , wherein the transparent boundary layer comprises a transparent conductive charge recombination layer that is electrically connected to each of the first and second photoactive layers.
4 . The photoactive device of claim 1 , wherein the boundary layer comprises a transparent conductive charge recombination layer disposed adjacent the first photoactive layer and a charge blocking layer disposed adjacent to the second photoactive layer, such that holes generated within one of the first and second photoactive layers combine with electrons generated within the other of the first and second photoactive layer, within the conductive charge recombination layer.
5 . A photoactive device, comprising:
first and second photoactive layers disposed between first and second electrodes, the first and second photoactive layers being separated by a recombination layer;
wherein the recombination layer that comprises a conductive material and is configured to selectively and substantially conduct electrons from but not to the first photoactive layer to but not from the second photoactive sublayer.
6 . A photoactive device, comprising:
a back electrode layer;
a transparent top electrode layer; and
a plurality of discrete photoactive layers disposed between the back electrode layer and the top electrode layer, wherein each of the plurality of photoactive layers is separated from each other photoactive layer by a charge recombination layer comprised of a material that is different from the photoactive layers.
7 . The photoactive device of claim 6 , wherein the recombination layer comprises a conductive metal layer.
8 . The photoactive device of claim 7 , wherein the recombination layer further comprises PEDOT-PSS.