Abstract:
The present disclosure relates to focusing luminescent concentrators wherein directional emission, obtained by placing an absorber/emitter within a microcavity or photonic crystal, may be oriented by a macroscopic concentrator and focused to a point or line for 3D or 2D concentration, respectively. The focusing luminescent concentrators disclosed herein may provide high concentration ratios without the need for tracking, and may reduce re-absorption losses associated with conventional concentrators. The present disclosure further relates to photovoltaic cells and/or optical detector devices comprising a focusing luminescent concentrator. The devices and methods presently disclosed are also useful, for example, in solar, thermal and thermophotovolatic applications.
Abstract:
There is disclosed squaraine compounds of formula I: wherein each of Y1 and Y2 is independently chosen from an optionally substituted amino group and an optionally substituted aryl group. Also described are organic optoelectronic devices comprising a Donor-Acceptor heterojunction that is formed from one or more of the squaraine compounds. A method of making the disclosed device, which may include one or more sublimation step for depositing said squaraine compound, is also disclosed.
Abstract:
The present disclosure relates to photosensitive optoelectronic devices comprising a compound blocking layer located between an acceptor material and a cathode, the compound blocking layer comprising: at least one electron conducting material, and at least one wide-gap electron conducting exciton blocking layer. For example, 3,4,9,10 perylenetetracarboxylic bisbenzimidazole (PTCBI) and 1,4,5,8-napthalene-tetracarboxylic-dianhydride (NTCDA) function as electron conducting and exciton blocking layers when interposed between the acceptor layer and cathode. Both materials serve as efficient electron conductors, leading to a fill factor as high as 0.70. By using an NTCDA/PTCBI compound blocking layer structure increased power conversion efficiency is achieved, compared to an analogous device using a conventional blocking layers shown to conduct electrons via damage-induced midgap states.
Abstract:
A patterned roller, and a method of making the patterned roller, is provided. A patterned roller may be made by first forming a first mold having a negative pattern by etching pits in a flat mold surface with an etching process. Then, a second mold is formed having a positive pattern, by pouring a first curable material into the first mold, curing the first curable material, and removing the first curable material from the first mold. Then the patterned roller having the negative pattern is formed by coating a roller with a layer of a second curable material, pre-curing the second curable material to provide a viscous but not hardened surface, and rolling the roller over the second mold to create the negative pattern in the second curable material. The second curable material is then cured. Any of the curable materials may be coated after curing, preferably with metal, to reduce sticking in subsequent steps. The patterned roller may be used to create a pattern of microlenses in a third curable material. A substrate is coated with the third curable material. The patterned roller is rolled over the third curable material to transfer the pattern to the third curable material. The third curable material may then be cured.
Abstract:
Systems and methods including bonding two or more separately formed circuit layers are provided using, for example, cold welding techniques. Processing techniques may be provided for combining inorganic and/or organic semiconductor devices in apparatus including, for example, microchips, optoelectronic devices, such as solar cells, photodetectors and organic light emitting diodes (OLEDs), and other apparatus with multi-layer circuitry. Methods of bonding preformed circuit layers may include the use of stamping and pressure bonding contacts of two or more circuit layers together. Such methods may find applicability, for example, in bonding circuitry to shaped substrates, including various rounded and irregular shapes, and may be used to combine devices with different structural properties, e.g. from different materials systems.
Abstract:
An organic photosensitive optoelectronic device includes an anode, a cathode, and a donor-acceptor heterojunction between the anode and the cathode, the heterojunction including a donor-like material and an acceptor-like material, wherein at least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound, wherein the subporphyrin or subporphyrazine compound includes boron.
Abstract:
There is disclosed ultrathin film material templating layers that force the morphology of subsequently grown electrically active thin films have been found to increase the performance of small molecule organic photovoltaic (OPV) cells. There is disclosed electron-transporting material, such as hexaazatriphenylene-hexacarbonitrile (HAT-CN) can be used as a templating material that forces donor materials, such as copper phthalocyanine (CuPc) to assume a vertical-standing morphology when deposited onto its surface on an electrode, such as an indium tin oxide (ITO) electrode. It has been shown that for a device with HAT-CN as the templating buffer layer, the fill factor and short circuit current of CuPc:C60 OPVs were both improved compared with cells lacking the HAT-CN template. This is explained by the reduction of the series resistance due to the improved crystallinity of CuPc grown onto the ITO surface.
Abstract:
An organic photosensitive device having an organic film with a desired crystalline order includes a first electrode layer and at least one structural templating layer disposed on the first electrode A photoactive region is disposed on the templating layer and includes a donor material and an acceptor material, wherein the donor or the acceptor is templated by the templating layer, and further wherein a majority of the molecules of the templated material are in a non-preferential orientation with respect to the first electrode An organic light emitting device incorporating such organic films includes a first electrode layer, a second electrode layer, at least one structural templating layer disposed between the first and second electrodes, and a functional layer disposed over the templating layer A majority of the molecules of the functional layer are in a non-preferential orientation with respect to the layer below the templating layer
Abstract:
Organic light emitting devices are described wherein the emissive layer comprises a host material containing an emissive molecule, which molecule is adapted to luminesce when a voltage is applied across the heterostructure, and the emissive molecule is selected from the group of phosphorescent organometallic complexes, including cyclometallated platinum, iridium and osmium complexes. The organic light emitting devices optionally contain an exciton blocking layer. Furthermore, improved electroluminescent efficiency in organic light emitting devices is obtained with an emitter layer comprising organometallic complexes of transition metals of formula L2MX, wherein L and X are distinct bidentate ligands. Compounds of this formula can be synthesized more facilely than in previous approaches and synthetic options allow insertion of fluorescent molecules into a phosphorescent complex, ligands to fine tune the color of emission, and ligands to trap carriers.
Abstract:
Light emitting devices are provided that include one or more OLEDs disposed only on a peripheral region of the substrate. An OLED may be disposed only on a peripheral region of a substantially transparent substrate and configured to emit light into the substrate. Another surface of the substrate may be roughened or include other features to outcouple light from the substrate. The edges of the substrate may be beveled and/or reflective. The area of the OLED(s) may be relatively small compared to the substrate surface area through which light is emitted from the device. One or more OLEDs also or alternatively may be disposed on an edge of the substrate about perpendicular to the surface of the substrate through which light is emitted, such that they emit light into the substrate. A mode expanding region may be included between each such OLED and the substrate.