Abstract: An OLED device comprises an anode and a cathode, and at least one graded emissive layer disposed between the anode and the cathode, the graded emissive layer comprising first and second materials, wherein a concentration of the first material increases continuously from an anode side of the graded emissive layer to a cathode side of the graded emissive layer, and a concentration of the second material decreases continuously from the anode side of the graded emissive layer to the cathode side of the graded emissive layer. An OLED device comprising a graded emissive layer and a hybrid white OLED device are also described.

Abstract: Disclosed herein are exciton-blocking treatments for buffer layers used in organic photosensitive optoelectronic devices. More specifically, the organic photosensitive optoelectronic devices described herein include at least one self-assembled monolayer disposed on the surface of an anode buffer layer. Methods of preparing these devices are also disclosed. The present disclosure further relates to methods of forming at least one self-assembled monolayer on a substrate.

Abstract: Organic photovoltaic cells (OPVs) and their compositions are described herein. one or more embodiments, the acceptor with an active layer of an OPV includes is a non-fullerene acceptor. Such non-fullerene acceptors may provide improved OPV performance characteristics such as improved power conversion efficiency, open circuit voltage, fill factor, short circuit current, and/or external quantum efficiency.

Abstract: An optoelectronic device comprises an anode, an emissive layer positioned over the anode, a charge generation layer stack positioned over the emissive layer, the charge generation layer stack comprising at least one hole transport layer and at least one electron transport layer positioned over the hole transport layer, and a cathode positioned over the charge generation layer stack. Other organic optoelectronic devices are also disclosed.

Abstract: The present disclosure generally relates to organic photosensitive optoelectronic devices and polaron pair recombination dynamics to impact efficiency and open circuit voltages of organic solar cells. The present disclosure also relates, in part, to methods of making organic photosensitive optoelectronic devices comprising the same.

Abstract: A highly efficient multi junction photovoltaic device, such as a two, three, or four junction device, is disclosed. The multi-junction device may include a first subcell comprising a first photoactive region and a second subcell comprising a second photoactive region. The first and second photoactive regions are designed to minimize spectral overlap and maximize photocurrent across a broad absorption spectra, such as wavelengths ranging from 400 nm to 900 nm. The device may further include an inter-connecting layer, disposed between the first subcell and the second subcell, that is at least substantially transparent. By introducing a transparent interconnecting layer, a dual element (tandem) cell achieves a power conversion efficiency of 10.0±0.5%. By adding an additional (3rd) sub-cell that absorbs at the second order optical interference maximum within the stack. The triple junction cell significantly improves the quantum efficiency at shorter wavelengths, achieving a power conversion efficiency of 11.1±0.

Abstract: There is disclosed ultrahigh-efficiency single- and multi-junction thin-film solar cells. This disclosure is also directed to a substrate-damage-free epitaxial lift-off (“ELO”) process that employs adhesive-free, reliable and lightweight cold-weld bonding to a substrate, such as bonding to plastic or metal foils shaped into compound parabolic metal foil concentrators. By combining low-cost solar cell production and ultrahigh-efficiency of solar intensity-concentrated thin-film solar cells on foil substrates shaped into an integrated collector, as described herein, both lower cost of the module as well as significant cost reductions in the infrastructure is achieved.

Abstract: An organic light emitting device comprises an anode and a cathode, at least one organic layer configured between the anode and the cathode, and at least one two-dimensional emissive layer configured between the anode and the cathode. A method of fabricating an organic light emitting device is also disclosed.

Abstract: Arrangements and techniques for providing organic emissive layers are provided, in which the emissive layer includes a first dopant having a dissociative energy level. A second dopant in the emissive layer provides a solid state sink energy level, to which doubly excited excitons and/or polarons may transition instead of to the dissociative energy level, thereby decreasing the undesirable effects of transitions to the dissociative energy level.

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: Devices, systems, and techniques are provided for improved OVJP deposition using a shutter disposed within the OVJP print head, between the print head inlet and the nozzle outlets. An OVJP print head as disclosed includes an inlet for organic material entrained in a carrier gas, a micronozzle array outlet, and a shutter disposed in the gas flow path between the inlet and the micronozzle array outlet. The shutter allows for rapid cutoff of carrier gas flow through the print head with extremely low latency.

Abstract: To reach high efficiencies, thermophotovoltaic cells must utilize the broad spectrum of a radiative thermal source. One promising approach to overcome this challenge is to have low-energy photons reflected and reabsorbed by the thermal emitter, where their energy can have another chance at contributing toward photogeneration in the cell. However, current methods for photon recuperation are limited by insufficient bandwidth or parasitic absorption, resulting in large efficiency losses relative to theoretical limits. This work demonstrates nearly perfect reflection of low-energy photons (˜99%) by embedding an air layer within the TPV cell. This result represents a four-fold reduction in parasitic absorption relative to existing TPV cells. As out-of-band reflectance approaches unity, TPV efficiency becomes nearly insensitive to cell bandgap and emitter temperature. Accessing this regime unlocks a range of possible materials and heat sources that were previously inaccessible to TPV energy conversion.

Abstract: A photovoltaic cell comprises an anode, a cathode, a first subcell positioned between the anode and the cathode, the first subcell comprising a first donor material and a first acceptor material, and a second subcell positioned between the first subcell and the cathode, the second subcell comprising a second donor material and a second acceptor material. A method of fabricating a photovoltaic cell is also described.

Abstract: High efficiency multi-junction small-molecule organic photovoltaic devices and methods of fabricating the same are disclosed herein. Design considerations for improving spectral coverage and light-harvesting efficiency using the multi-junction devices are also disclosed.

Abstract: The present invention relates in part to an asymmetric non-fullerene acceptor compound for use in organic photovoltaic (OPV) devices. The invention also relates in part to an OPV device comprising an asymmetric non-fullerene acceptor compound.

Abstract: Disclosed herein are organic photosensitive optoelectronic devices comprising two electrodes in superposed relation, a photoactive region located between the two electrodes, wherein the photoactive region comprises a donor mixture and an organic acceptor material, the donor mixture comprising at least one organic polymer donor material and at least one squaraine donor. Methods of fabricating the organic photosensitive optoelectronic devices are also disclosed.

Abstract: Disclosed herein are organic photosensitive optoelectronic devices comprising two electrodes in superposed relation; a mixed photoactive layer located between the two electrodes, wherein the mixed photoactive layer comprises at least one donor material having a HOMO energy and at least one acceptor material having a LUMO energy, wherein the at least one donor material and the at least one acceptor material form a mixed donor-acceptor heterojunction; a photoactive layer adjacent to and interfacing with the mixed photoactive layer, wherein the photoactive layer comprises a material having a LUMO energy within 0.3 eV of the LUMO energy of the at least one acceptor material or a HOMO energy within 0.3 eV of the HOMO energy of the at least one donor material; and a buffer layer adjacent to and interfacing with the mixed photoactive layer.

Abstract: A high efficiency small molecule tandem solar cell is disclosed. The tandem cell may include a first subcell comprising a first photoactive region and a second subcell comprising a second photoactive region. The first and second photoactive regions are designed to minimize spectral overlap and maximize photocurrent. The device may further include an interconnecting layer, disposed between the first subcell and the second subcell, that is at least substantially transparent.

Abstract: A method is presented for fabricating a substrate comprised of a compound semiconductor. The method includes: growing a sacrificial layer onto a parent substrate; growing an epitaxial template layer on the sacrificial layer; removing the template layer from the parent substrate using an epitaxial lift-off procedure; and bonding the removed template layer to a host substrate using Van der Waals forces and thereby forming a compound semiconductor substrate.

Abstract: The present disclosure relates to a photosensitive optoelectronic device comprising two electrodes, an inorganic subcell positioned between the two electrodes, wherein the inorganic subcell comprises at least one inorganic semiconductor material having a band gap energy (EG), and an organic sensitizing window layer disposed on the inorganic subcell. In one aspect, the organic sensitizing window layer comprises a singlet fission material. In another aspect, the organic sensitizing window layer comprises a singlet fission host and a phosphorescent emitter dopant, where the singlet fission host exhibits an excitation triplet energy (ET-SF) greater than or equal to an excitation triplet energy (ET-PE) exhibited by the phosphorescent emitter dopant.