Provided is a light-emitting diode and a method for preparing the same. The light-emitting diode includes an anode, a hole transport layer, a perovskite light-emitting layer, an electron transport layer and a cathode stacked in sequence, in which the perovskite light-emitting layer includes a first sublayer and a second sublayer stacked in sequence, with a material for forming the first sublayer including an inorganic perovskite material, and with a material for forming the second sublayer being an organic perovskite material.

Provided is a light-emitting diode and a method for preparing the same. The light-emitting diode includes an anode, a hole transport layer, a perovskite light-emitting layer, an electron transport layer and a cathode stacked in sequence, in which the perovskite light-emitting layer includes a first sublayer and a second sublayer stacked in sequence, with a material for forming the first sublayer including an inorganic perovskite material, and with a material for forming the second sublayer being an organic perovskite material.

Disclosed are an organic proton-type ionic liquid, a film with a two-dimensional perovskite pure-phase quantum well structure, a preparation method and use thereof. The chemical formula of the organic proton-type alkylamine acetate ionic liquid is RNH.sub.3.sup.+—RCOO.sup.−, where R represents an alkyl group of C4-8 or a phenyl group, preferably, the chemical formula of the organic proton-type alkylamine acetate ionic liquid is CH.sub.3(CH.sub.2).sub.3NH.sub.3.sup.+—CH.sub.2COO.sup.−. The organic proton-type alkylamino acetate ionic liquid disclosed in the present disclosure can be used to prepare perovskite material, the prepared perovskite film thereby can form a pure-phase single quantum well, and the crystal grain size of the film can reach the level of micrometers or even millimeters.

A light-emitting element contains negative ions and positive ions, and includes a solid ionic layer, a layer containing quantum dots, and a cathode electrode and an anode electrode. The ionic layer includes a p-type doped region on the anode electrode side containing the negative ions in a higher quantity than the positive ions, an n-type doped region on the cathode electrode side containing the positive ions in a higher quantity than the negative ions, and a junction region between the p-type doped region and the n-type doped region. The layer containing the quantum dots is adjacent to the junction region. Alternatively, the quantum dots are contained in the junction region. Alternatively, the quantum dots are adjacent to the junction region.

An organic light-emitting device having a perovskite layer having a thickness of 50 nm or more has a low drive voltage and a high power efficiency, and can suppress interelectrode short-circuiting and current leakage.

A display device includes a first substrate having a first surface and a second surface opposite to the first surface, a first light-emitting layer including a first polymer and an ionic liquid on the second surface, a first electrode provided on a first side surface of the first light-emitting layer, a second electrode provided on a second side surface of the first light-emitting layer opposite to the first side surface of the first light-emitting layer, and a second substrate in contact with the first light-emitting layer opposite to the first substrate.

A method for preparing three-dimensional perovskite nanopixels of a digital display is provided. The method includes steps of preparing precursor ink by mixing methylammonium halide and lead halide and adding them into another mixture, adding the precursor ink into a nanopipette, placing the nanopipette with the precursor ink above a silicon substrate and apart from the silicon substrate by a certain distance, configuring the nanopipette to come into contact with the Si substrate such that a portion of the precursor ink having an interface surface of a shape of a meniscus is formed between the nanopipette and the silicon substrate, performing rapid evaporation of the portion of the precursor ink to facilitate crystallization of perovskite, moving the nanopipette upwardly at a constant speed such that the crystallization of perovskite proceeds upwardly, and terminating the crystallization of perovskite to generate a freestanding nanopixel for emitting light.

A method for preparing three-dimensional perovskite nanopixels of a digital display is provided. The method includes steps of preparing precursor ink by mixing methylammonium halide and lead halide and adding them into another mixture, adding the precursor ink into a nanopipette, placing the nanopipette with the precursor ink above a silicon substrate and apart from the silicon substrate by a certain distance, configuring the nanopipette to come into contact with the Si substrate such that a portion of the precursor ink having an interface surface of a shape of a meniscus is formed between the nanopipette and the silicon substrate, performing rapid evaporation of the portion of the precursor ink to facilitate crystallization of perovskite, moving the nanopipette upwardly at a constant speed such that the crystallization of perovskite proceeds upwardly, and terminating the crystallization of perovskite to generate a freestanding nanopixel for emitting light.

Disclosed herein are new electrochromic materials, including small molecule, oligomeric, and polymeric electrochromic materials, and compositions comprising the electrochromic materials and a salt. Further disclosed are electrochromic devices prepared from the electrochromic materials and electrochromic material compositions. Also disclosed are melt processable polymeric electrochromic materials, melt processable compositions comprising the melt processable polymeric electrochromic material, and a salt; and devices prepared therefrom.

The present invention discloses a light-emitting electrochemical cell, which includes a first electrode, a light-emitting layer, and a second electrode which are stacked, wherein the light-emitting layer includes a light-emitting material and an ion conductive polymer. The present invention also discloses an electroluminescent display device, including a glass substrate, a thin film transistor, a light-emitting electrochemical cell, a protective layer, and a polarizer. Embodiments of the present application provide a light-emitting electrochemical cell and an electroluminescence display device, wherein the electro-luminescence display device is construed by providing a simple structure and manufacturing process to the light-emitting electrochemical cell, and therefore the manufacturing cost is reduced, and the production efficiency is improved.