Provided is a method for preparing lead iodide, which controls the crystal form of lead iodide through temperature, including: dissolving a lead compound in a first acid solution and adding an iodine compound to form a reaction solution including the first lead iodide; and heating the reaction solution to a temperature of 60° C. or more and standing at a constant temperature, to obtain the second lead iodide, wherein a peak intensity of the (003) crystal plane of the second lead iodide is greater than or equal to a peak intensity of the (110) crystal plane. Provided is also a method for preparing the perovskite film.

Provided is a method for preparing lead iodide, which controls the crystal form of lead iodide through temperature, including: dissolving a lead compound in a first acid solution and adding an iodine compound to form a reaction solution including the first lead iodide; and heating the reaction solution to a temperature of 60° C. or more and standing at a constant temperature, to obtain the second lead iodide, wherein a peak intensity of the (003) crystal plane of the second lead iodide is greater than or equal to a peak intensity of the (110) crystal plane. Provided is also a method for preparing the perovskite film.

A method of preparing a carbon nanotube monolayer film includes applying a bifunctional hydrogen-bond linker onto a substrate to prepare a surface-treated substrate, mixing carbon nanotubes having a heteroatom-containing aromatic polymer coating film with a hydrophobic solvent to obtain a composition and contacting the surface-treated substrate with the composition, and heat-treating the surface-treated substrate contacting the composition.

The present disclosure provides a back plate for OLED display substrate, and a method for manufacturing the same. The back plate comprises a pixel definition layer comprising a body layer and an interface layer disposed on the surface of the body layer. The interface layer exhibits different lyophilic or lyophobic properties with respect to a functional layer of the OLED depending on the temperature of the interface layer. When the OLED display substrate is manufactured by using the back plate according the present disclosure, the cost can be reduced, and the device yield of the display substrate can be ensured.

An electron transport composition includes a metal oxide and a photoacid generator, wherein the photoacid generator has at least one of a halogenated triazine-based compound or an oxime sulfonate-based compound. When the electron transport composition is applied to a light-emitting element, the light-emitting element may exhibit improved luminous efficiency characteristics and element lifespan characteristics.

A method for manufacturing a display module that is variable from a first state, which is unfolded, to a second state, which is folded with respect to a folding axis, may include folding the display module into a third state that is different from the second state, and performing a first heat treatment on the display module in the third state at a first temperature.

Provided are an inverted thick 2D hybrid perovskite solar cell insensitive to film thickness and a preparation method thereof, belonging to the field of organic-inorganic hybrid perovskite materials. The solar cell adopts a 2D hybrid perovskite thick-film material as a light absorption layer having thickness in a range of 500-800 nm, which is conducive to the full absorption of sunlight. The thick-film film material can be deposited from a precursor solution added with guanidine hydroiodide, and is composed of large grains growing along the thickness direction. The solar cell with an inverted structure prepared by using the thick-film material as a light absorption layer has an efficiency fluctuation less than 5% in a film thickness range of 500-800 nm. This is of great value for the preparation of high-performance hybrid perovskite solar cells by a large-area solution method.

The present invention discloses a thin-film light-emitting device including a charge generating junction layer and a method of fabricating the thin-film light-emitting device. The thin-film light-emitting device including a charge generating junction layer according to one embodiment of the present invention includes a negative electrode; at least one light-emitting unit formed on the negative electrode and including a charge generating junction layer, an electron injection/transport layer, a thin-film light-emitting layer, and a hole injection/transport layer in a sequential order; and a negative electrode formed on the light-emitting unit. In the thin-film light-emitting device of the present invention, the charge generating junction layer has a layer-by-layer structure in which a p-type semiconductor layer and an n-type semiconductor layer are formed, and the concentration of oxygen vacancies at the interface between the p-type and n-type semiconductor layers is adjusted by annealing the n-type semiconductor layer.

Self-organizing patterns with micrometer-scale feature sizes are promising for the large area fabrication of photonic devices and scattering layers in optoelectronics. Pattern formation would ideally occur in the active semiconductor to avoid the need for further processing steps. The present disclosure includes approaches to form period patterns in single layers of organic semiconductors by an annealing process. When heated, a crystallization front propagates across the film, producing a sinusoidal surface structure with wavelengths comparable to that of near-infrared light. These surface features form initially in the amorphous region within a micron of the crystal growth front, likely due to competition between crystal growth and surface mass transport. The pattern wavelength can be tuned by varying film thickness and annealing temperature, millimeter scale domain sizes are obtained. Aspects of the disclosure can be exploited for self-assembly of microstructured organic optoelectronic devices, for example.

An electroluminescent device includes a first electrode and a second electrode facing each other, and a light emitting layer disposed between the first electrode and the second electrode, where the light emitting layer includes a first light emitting layer including a first quantum dot and a second light emitting layer including a second quantum dot and an n-type metal oxide.