Abstract:
An organic photovoltaic cell includes an anode and a cathode, and a plurality of organic semiconductor layers between the anode and the cathode. At least one of the anode and the cathode is transparent. Each two adjacent layers of the plurality of organic semiconductor layers are in direct contact. The plurality of organic semiconductor layers includes an intermediate layer consisting essentially of a photoconductive material, and two sets of at least three layers. A first set of at least three layers is between the intermediate layer and the anode. Each layer of the first set consists essentially of a different organic semiconductor material having a higher LUMO and a higher HOMO, relative to the material of an adjacent layer of the plurality of organic semiconductor layers closer to the cathode. A second set of at least three layers is between the intermediate layer and the cathode. Each layer of the second set consists essentially of a different organic semiconductor material having a lower LUMO and a lower HOMO, relative to the material of an adjacent layer of the plurality of organic semiconductor layers closer to the anode.
Abstract:
Organic photosensitive optoelectronic devices are disclosed. The devises are thin-film crystalline organic optoelectronic devices capable of generating a voltage when exposed to light, and prepared by a method including the steps of: depositing a first organic layer over a first electrode; depositing a second organic layer over the first organic layer; depositing a confining layer over the second organic layer to form a stack; annealing the stack; and finally depositing a second electrode over the second organic layer.
Abstract:
A first device is provided. The device includes an organic semiconductor laser. The organic semiconductor laser further includes an optical cavity and an organic layer disposed within the optical cavity. The organic layer includes: an organic host compound; an organic emitting compound capable of fluorescent emission; and an organic dopant compound. The organic dopant compound may also be referred to herein as a “triplet manager.” The triplet energy of the organic dopant compound is lower than or equal to the triplet energy of the organic host compound. The triplet energy of the organic dopant compound is lower than or equal to the triplet energy of the organic emitting compound. The singlet energy of the organic emitting compound is lower than or equal to the singlet energy of the organic host compound.
Abstract:
There is disclosed a method for preparing the surface of a metal substrate. The present disclosure also relates to an organic photovoltaic device comprising a metal substrate made by such method. Also disclosed herein is an inverted photosensitive device comprising a reflective electrode comprising stainless steel foil, an organic donor-acceptor heterojunction over the reflective electrode, and a transparent electrode over the donor-acceptor heterojunction.
Abstract:
A photosensitive optoelectronic device having an improved hybrid planar bulk heterojunction includes a plurality of photoconductive materials disposed between the anode and the cathode. The photoconductive materials include a first continuous layer of donor material and a second continuous layer of acceptor material. A first network of donor material or materials extends from the first continuous layer toward the second continuous layer, providing continuous pathways for conduction of holes to the first continuous layer. A second network of acceptor material or materials extends from the second continuous layer toward the first continuous layer, providing continuous pathways for conduction of electrons to the second continuous layer. The first network and the second network are interlaced with each other. At least one other photoconductive material is interspersed between the interlaced networks. This other photoconductive material or materials has an absorption spectra different from the donor and acceptor materials.
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:
A photoactive device is provided. The device includes a first electrode, a second electrode, and a photoactive region disposed between and electrically connected to the first and second electrodes. The photoactive region further includes an organic donor layer and an organic acceptor layer that form a donor-acceptor heterojunction. The mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region are different by a factor of at least 100, and more preferably a factor of at least 1000. At least one of the mobility of holes in the organic donor region and the mobility of electrons in the organic acceptor region is greater than 0.001 cm2/V-sec, and more preferably greater than 1 cm2/V-sec. The heterojunction may be of various types, including a planar heterojunction, a bulk heterojunction, a mixed heterojunction, and a hybrid planar-mixed heterojunction.
Abstract:
A multicolor organic light emitting device employs vertically stacked layers of double heterostructure devices which are fabricated from organic compounds. The vertical stacked structure is formed on a glass base having a transparent coating of ITO or similar metal to provide a substrate. Deposited on the substrate is the vertical stacked arrangement of three double heterostructure devices, each fabricated from a suitable organic material. Stacking is implemented such that the double heterostructure with the longest wavelength is on the top of the stack. This constitutes the device emitting red light on the top with the device having the shortest wavelength, namely, the device emitting blue light, on the bottom of the stack. Located between the red and blue device structures is the green device structure. The devices are configured as stacked to provide a staircase profile whereby each device is separated from the other by a thin transparent conductive contact layer to enable light emanating from each of the devices to pass through the semitransparent contacts and through the lower device structures while further enabling each of the devices to receive a selective bias. The devices are substantially transparent when de-energized, making them useful for heads-up display applications.
Abstract:
Methods of transferring a metal and/or organic layer from a patterned stamp, preferably a soft, elastomeric stamp, to a substrate are provided. The patterned metal or organic layer may be used for example, in a wide range of electronic devices. The present methods are particularly suitable for nanoscale patterning of organic electronic components.
Abstract:
A method of processing bundles of carbon nanotubes (CNTs). Bundles of CNTs are put into a solution and unbundled using sonication and one or more surfactants that break apart and disperse at least some of the bundles into the solution such that it contains individual semiconducting CNTs, individual metallic CNTs, and remaining CNT bundles. The individual CNTs are separated from each other using agarose bead column separation using sodium dodecyl sulfate as a surfactant. Remaining CNT bundles are then separated out by performing density-gradient ultracentrifugation.