A polymer solar cell including a cathode buffer layer (CBL) is proposed. the CBL may include a reaction product between a conjugate polymer electrolyte and an acid derivative, the conjugate polymer electrolyte is poly [(9,9-bis 3′-(N,N-dimethylamino) propyl)-2,7-fluorene)-alt-2,7-(9,9-dihexylfluorene)] (PFN), and the acid derivative is trifluoroacetic acid (CF3AA), 4-trifluoromethyl benzoic acid (CF3BA), or 4-toluene sulfonic acid (TsOH). The CBL including the conjugate polymer electrolyte (PFN) modified with a specific acid derivative may improve short-circuit current (J.sub.sc) and a filling factor (FF) simultaneously, and thus, significantly improved efficiency is exhibited.

The present invention is to provide a photoelectric conversion element with an excellent sensitivity, an imaging element, an optical sensor, and a compound. The photoelectric conversion element according to the embodiment of the present invention includes, in the following order, a conductive film, a photoelectric conversion film, and a transparent conductive film, in which the photoelectric conversion film contains a compound represented by Formula (1) and a coloring agent.

A-D-A  (1)

The present disclosure relates to a device that includes a first layer that includes at least one of a semiconducting material, a hole transport material (HTM), and/or an electron transport material (ETM), a second layer, and a third layer that includes a material that is at least one of transparent or conductive, where the second layer is positioned between the first layer and the third layer, the first layer, the second layer, and the third layer are in electrical contact with each other, and the third layer has a first thickness between greater than zero nm and about 100 nm. In some embodiments of the present disclosure, the semiconducting material may include a perovskite.

An organic field effect transistor includes a channel structure having a photoalignment layer and an organic semiconductor layer disposed directly over the photoalignment layer, where a charge carrier mobility varies along a thickness direction of the channel structure. The channel structure may define an active area between a source and a drain of the transistor and may include alternating layers of at least two photoalignment layers and at least two organic semiconductor layers. Each photoalignment layer is configured to influence an orientation of molecules within an overlying organic semiconductor layer and hence impact the mobility of charge carriers within the device active area while also advantageously decreasing the OFF current of the device.

Provided is an organic light emitting diode display device. The organic light emitting diode display device includes a flexible substrate, including a display region, a first barrier region and a second barrier region, wherein the first barrier region is located between the display region and the second barrier region, and a barrier is disposed on the flexible substrate of the second barrier region; wherein a groove is formed in the flexible substrate of the first barrier region, and an organic light emitting diode unit is disposed on the flexible substrate of the display region.

The present invention relates to a novel fluorene derivative having a structure of formula (I): wherein X is independently selected from a group consisting of Cl, Br, I, trifluoromethanesulfonate and 4-(trifluoromethyl)benzenesulfonate; Y is a group of formula —(CH.sub.2).sub.n— where n is an integer ranging from 3 to 12; and R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are independently selected from a group consisting of tert-butyl group, triphenylamine, carbazole and carbazole derivative. The invention further relates to a polymer obtained from the said novel fluorene derivative and methods for preparing the same, as well as their uses as materials for an organic light-emitting diode device.

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A conductive polymer composition containing: a composite containing a π-conjugated polymer (A) and a polymer (B) shown by the following general formula (2); H.sub.2O (D) for dispersing the composite; and a water-soluble organic solvent (C). This provides a composition which has favorable filterability and film formability, and which is capable of relieving acidity and forming a conductive film with high transparency. Moreover, since the H.sub.2O dispersion of the conductive polymer compound is mixed with an organic solvent, the surface tension and the contact angle are so low that leveling property on a substrate is imparted. The composition is usable in droplet-coating methods. Since an organic solvent having a higher boiling point than H.sub.2O is used as the organic solvent, the composition can avoid solid content precipitation around a nozzle and solid content precipitation due to drying between ejecting the liquid material from a nozzle tip and landing on a substrate.

##STR00001##

A device includes a first substrate, a silicon layer supported by the first substrate, and an active glass layer with a layer including a crystal material with a chemical formula ABX.sub.3 supported by a glass substrate. The active glass layer is stacked on the first substrate such that the layer including the crystal material with a chemical formula ABX.sub.3 and silicon layer are arranged between the first substrate and the glass substrate.

A method for preparing a wavelength converting film is disclosed. The method comprising mixing at least one phosphor, a polysiloxane and optionally an organic solvent, thereby preparing a mixture, placing the mixture on a substrate, pre-curing the mixture on the substrate, thereby preparing a wavelength converting film. Furthermore, a wavelength converting film is disclosed, a method for preparing a light-emitting device and a light-emitting device.

A method for preparing a wavelength converting film is disclosed. The method comprising mixing at least one phosphor, a polysiloxane and optionally an organic solvent, thereby preparing a mixture, placing the mixture on a substrate, pre-curing the mixture on the substrate, thereby preparing a wavelength converting film. Furthermore, a wavelength converting film is disclosed, a method for preparing a light-emitting device and a light-emitting device.