Organic photovoltaic device having a lateral charge transport channel
Organic photovoltaic cells (OPVs) and their compositions are described herein. In one or more embodiments, the OPV or solar cell includes a first electrode (e.g., cathode); a second electrode (e.g., anode); an active layer positioned between the first electrode and the second electrode; and a channel layer positioned between the first electrode and the active layer, wherein the channel layer is configured to laterally disperse a charge across the channel layer. In certain examples, the first electrode is arranged in a grid structure having a plurality of electrode segments and a respective opening between adjacent segments of the first electrode.
1. An optoelectronic device, comprising:
an anode;
a cathode arranged in a grid structure having a plurality of electrode segments and a respective opening between adjacent segments of the cathode;
an active layer positioned between the anode and the cathode, the active layer comprising at least one organic donor material and at least one acceptor material; and
a channel layer positioned between the cathode and the active layer, wherein the channel layer is configured to laterally disperse a charge across the channel layer;
an electron blocking layer positioned between the channel layer and the cathode, in direct contact with the channel layer and the cathode;
wherein an interface between the active layer and the channel layer has an energy barrier of at least 0.1 eV, configured to confine electrons within the channel layer.
2. The optoelectronic device of claim 1 , the channel layer comprising fullerene.
3. The optoelectronic device of claim 2 , wherein the channel layer has a neat fullerene composition.
4. The optoelectronic device of claim 3 , wherein the neat fullerene composition is C 60 or C 70 .
5. The optoelectronic device of claim 1 , wherein the channel layer has a thickness of between 1 nm and 25 nm.
6. The optoelectronic device of claim 1 , wherein the electron blocking layer is a neat electron blocking layer.
7. The optoelectronic device of claim 1 , wherein the electron blocking layer is a mixed electron blocking layer.
8. The optoelectronic device of claim 1 , wherein the electron blocking layer comprises a material selected from the group consisting of BPhen and fullerene.
9. The optoelectronic device of claim 1 , wherein the electron blocking layer has a thickness of between 5 nm and 15 nm.
10. The optoelectronic device of claim 1 , wherein the electron blocking layer comprises a 1:1 volumetric ratio of fullerene and BPhen.
11. The optoelectronic device of claim 1 , wherein a diffusion constant D of the channel layer is at least 0.5 cm 2 /s.
12. The optoelectronic device of claim 1 , wherein the at least one donor material is selected from the group consisting of DTDCPB and DTDCTB.
13. The optoelectronic device of claim 1 , wherein the at least one acceptor material is fullerene.
14. The optoelectronic device of claim 1 , wherein the optoelectronic device comprises an organic photovoltaic cell having a power conversion efficiency of at least 12%.
15. The optoelectronic device of claim 1 , wherein the optoelectronic device comprises an organic photovoltaic cell having a power conversion efficiency of at least 14%.
16. A product comprising the optoelectronic device of claim 1 , wherein the product is selected from the group consisting of a photovoltaic cell, a charge-coupled device, and a photosensor.
17. The optoelectronic device of claim 1 , wherein the device has a photocurrent response of at least 5% to incident light received at an opening between the grid electrode segments, at a distance of 1 cm away from any grid electrode segment.