An OLED, a method for fabricating the same, and a display device are disclosed. The OLED includes a first electrode, a first carrier transporting layer, an organic light emitting layer, a second carrier transporting layer, a second electrode, and a light extracting layer between the first electrode and the organic light emitting layer. The light extracting layer is made from a first carrier transporting material. The light extracting layer is formed between the first electrode and the organic light emitting layer at a light exit side of the OLED, and is formed from the first carrier transporting material. This increases the light extracting efficiency of the OLED. The light extracting layer further acts as the first carrier transporting layer, thus simplifying the structure of OLED, making OLED easy to fabricate, and efficiently controlling cost.

The present application discloses a self-luminous apparatus including: a first electrode layer, a second electrode layer, a light emitting layer between the first electrode layer and the second electrode layer, and an insulating layer between or outside the first electrode layer and the first substrate; wherein, at least one layer of the insulating layer, the first electrode layer and the second electrode layer is produced a hybrid structure having mixed material with high and low refractive index by the changes of the temperature and/or pressure and chemical vapor deposition to improve light emission efficiency. The present application also discloses a method to manufacturing the self-luminous apparatus and a display apparatus. By the way mentioned above, making the light pass the hybrid structure having mixed material with high and low refractive index to scattering or refraction light, reducing the total reflection of light and improve the light transmittance of the apparatus.

The invention provides an optoelectronic device comprising a photoactive region, which photoactive region comprises: an n-type region comprising at least one n-type layer; a p- type region comprising at least one p-type layer; and, disposed between the n-type region and the p-type region: a layer of a perovskite semiconductor without open porosity. The perovskite semiconductor is generally light-absorbing. In some embodiments, disposed between the n-type region and the p-type region is: (i) a first layer which comprises a scaffold material, which is typically porous, and a perovskite semiconductor, which is typically disposed in pores of the scaffold material; and (ii) a capping layer dis -posed on said first layer, which capping layer is said layer of a perovskite semiconductor without open porosity, wherein the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer. The layer of the perovskite semiconductor without open porosity (which may be said capping layer) typically forms a planar heterojunction with the n-type region or the p-type region. The invention also provides processes for producing such optoelectronic devices which typically involve solution deposition or vapour deposition of the perovskite. In one embodiment, the process is a low temperature process; for instance, the entire process may be performed at a temperature or temperatures not exceeding 150° C.

Disclosed herein are methods for fabricating an organic photovoltaic device comprising depositing an amorphous organic layer and a crystalline organic layer over a first electrode, wherein the amorphous organic layer and the crystalline organic layer contact one another at an interface; annealing the amorphous organic layer and the crystalline organic layer for a time sufficient to induce at least partial crystallinity in the amorphous organic layer; and depositing a second electrode over the amorphous organic layer and the crystalline organic layer. In the methods and devices herein, the amorphous organic layer may comprise at least one material that undergoes inverse-quasi epitaxial (IQE) alignment to a material of the crystalline organic layer as a result of the annealing.

A tandem cell is provided in the present disclosure, which relates to the technical field of photovoltaics, so as to form a functional layer with high film ordering on a bottom cell, thereby improving photoelectric conversion efficiency of the tandem cell. The tandem cell includes: a bottom cell with a textured surface; a hole transport layer formed on the textured surface of the bottom cell; a second ordered induction layer and a perovskite absorption layer formed on the hole transport layer, the second ordered induction layer being located between the hole transport layer and the perovskite absorption layer; and a transparent conductive layer formed on the perovskite absorption layer. An inducing material contained in the second ordered induction layer is organic ammonium salt or inorganic lead compound. The tandem cell according to the present disclosure is a tandem cell with a perovskite solar cell as a top cell.

A tandem cell is provided in the present disclosure, which relates to the technical field of photovoltaics, so as to form a functional layer with high film ordering on a bottom cell, thereby improving photoelectric conversion efficiency of the tandem cell. The tandem cell includes: a bottom cell with a textured surface; a hole transport layer formed on the textured surface of the bottom cell; a second ordered induction layer and a perovskite absorption layer formed on the hole transport layer, the second ordered induction layer being located between the hole transport layer and the perovskite absorption layer; and a transparent conductive layer formed on the perovskite absorption layer. An inducing material contained in the second ordered induction layer is organic ammonium salt or inorganic lead compound. The tandem cell according to the present disclosure is a tandem cell with a perovskite solar cell as a top cell.

Provided is a composition for a hole collecting layer of an organic photoelectric conversion element, the composition containing a solvent and an electron transporting substance comprising a polythiophene derivative that includes a repeating unit represented by formula (1) or formula (1′).

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(In formula (1) and formula (1′), R.sup.1 denotes an alkyl group having 1-6 carbon atoms or a fluorine atom. In formula (1), M denotes a hydrogen atom, an alkali metal selected from the group consisting of Li, Na and K, NH(R.sup.2).sub.3 or HNC.sub.5H.sub.5. R.sup.2 groups are each independently a hydrogen atom or an optionally substituted alkyl group having 1-6 carbon atoms.)

An organic light-emitting device including an anode electrode, a hole injection layer on the anode electrode, a hole transport layer on the hole injection layer, an emissive layer on the hole transport layer, and a cathode electrode on the emissive layer. A material of the hole injection layer includes a nitrogen-containing compound having a quinoid structure and a nitrogen-containing compound having a benzenoid structure. A ratio of a peak intensity I.sub.B to a peak intensity I.sub.A (I.sub.B/I.sub.A) in a Fourier transform infrared spectroscopy (FTIR) spectrum of the material of the hole injection layer ranges from 1.5 to 2.5, the peak intensity I.sub.A and the peak intensity I.sub.B being further defined.

Measurements on organic single crystals reveal remarkable optical and electrical characteristics compared to disordered films but practical device applications require uniform, pinhole-free films. Disclosed herein is a process to reliably convert as-deposited amorphous thin films to ones that are highly crystalline, with grains on the order of hundreds of microns. The disclosed method results in films that are pinhole-free and that possess grains that individually are single crystal domains.

The present invention relates to nanoparticles of π-conjugated polymers. The present invention also relates to an aqueous composition comprising these polymeric nanoparticles, to processes for making the nanoparticles, and to the use of these nanoparticles in the fabrication of electronic devices and components.