The present invention relates to compounds of formula (1) which are suitable for use in electronic devices, especially in organic electroluminescent devices.

The present invention concerns a device for room temperature reverse-bias operation photo-detection. The device comprising:—a planar first electrode extending in a planar direction;—a second electrode positioned above the first electrode in a direction substantially perpendicular to said planar direction; and—an active region sandwiched between the first and second electrode. The active region consists of a light absorbing perovskite and wherein the light absorbing perovskite is in direct contact with at least one of the first and second electrodes.

The invention provides an optoelectronic device comprising a mixed-anion perovskite, wherein the mixed-anion perovskite comprises two or more different anions selected from halide anions and chalcogenide anions. The invention further provides a mixed-halide perovskite of the formula (I) [A][B][X].sub.3 wherein: [A] is at least one organic cation; [B] is at least one divalent metal cation; and [X] is said two or more different halide anions. In another aspect, the invention provides the use of a mixed-anion perovskite as a sensitizer in an optoelectronic device, wherein the mixed-anion perovskite comprises two or more different anions selected from halide anions and chalcogenide anions. The invention also provides a photosensitizing material for an optoelectronic device comprising a mixed-anion perovskite wherein the mixed-anion perovskite comprises two or more different anions selected from halide anions and chalcogenide anions.

A formulation for use in the preferential formation of thin films of a perovskite material AMX 3 with a certain required crystalline structure, wherein said formulation comprises two or more compounds which between them comprise one or more first organic cations A; one or more metalcations M; one or more second cations A′; one or more first anions X and one or more second anions X′.

Photovoltaic devices such as solar cells, hybrid solar cell-batteries, and other such devices may include an active layer disposed between two electrodes. The active layer may have perovskite material and other material such as mesoporous material, interfacial layers, thin-coat interfacial layers, and combinations thereof. The perovskite material may be photoactive. The perovskite material may be disposed between two or more other materials in the photovoltaic device. Inclusion of these materials in various arrangements within an active layer of a photovoltaic device may improve device performance. Other materials may be included to further improve device performance, such as, for example: additional perovskites, and additional interfacial layers.

A method for preparing a composite material, including the following steps: providing metal oxide nanoparticles and a polyaromatic compound having a structure represented by Formula I,

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where, Ar.sub.1, Ar.sub.2, Ar.sub.3, and Ar.sub.4 are selected from aromatic rings; X.sub.1, X.sub.2, and X.sub.3 are selected from active groups configured for binding with the metal oxide nanoparticles, each of R.sub.1, R.sub.2, and R.sub.3 independently contains at least one of alkylene, amine, —N═N—, alkenyl, alkynyl, and phenyl, and each of m, n, and y is independently selected from 0 or positive integers; dispersing the polyaromatic compound and the metal oxide nanoparticles in a solvent to yield a mixed solution; and heating the mixed solution to yield the composite material. A composite material includes: a polyaromatic compound and metal oxide nanoparticles. The polyaromatic compound is connected to the metal oxide nanoparticles. The polyaromatic compound has a structure represented by Formula I.

The present disclosure relates to a display substrate and a display device. The display substrate includes: a base substrate including a display area and a non-display area includes a fan-out area; a signal line layer including a plurality of signal lines located in the fan-out area; a first metal layer including a first power line located in the non-display area; a first electrode layer including a first electrode portion; and an organic insulating layer having a groove located in the non-display area. On the base substrate, an orthographic projection of the first electrode portion at least partially overlaps with that of the first power line, an orthographic projection of the organic insulating layer at an edge of the groove at least partially overlaps with that of the fan-out area in a first overlapping area having at least part not overlapping with an orthographic projection of the first electrode portion.

The present invention relates to a process for producing a layer of a crystalline material, which process comprises disposing on a substrate: a first precursor compound comprising a first cation and a sacrificial anion, which first cation is a metal or metalloid cation and which sacrificial anion comprises two or more atoms; and a second precursor compound comprising a second anion and a second cation, which second cation can together with the sacrificial anion form a first volatile compound. The invention also relates to a layer of a crystalline material obtainable by a process according to the invention. The invention also provides a process for producing a semiconductor device comprising a process for producing a layer of a crystalline material according to the invention. The invention also provides a composition comprising: (a) a solvent; (b) NH.sub.4X; (c) AX; and (d) BY.sub.2 or MY.sub.4; wherein X, A, M and Y are as defined herein.

Composition for use in an organic light-emitting device, the composition having a fluorescent light-emitting material and a triplet-accepting material subject to the following energetic scheme: 2×T.sub.1A>S.sub.1A>S.sub.1E, or T.sub.1A+T.sub.1E>S.sub.1A>S.sub.1E in which: T1A represents a triplet excited state energy level of the triplet-accepting material; TIE represents a triplet excited state energy level of the light-emitting material; S.sub.1A represents a singlet excited state energy level of the triplet-accepting material; and S.sub.1E represents a singlet excited state energy level of the light-emitting material; and in which light emitted by the composition upon excitation includes delayed fluorescence.

An organic compound with characteristics excelling in hole-injecting/transporting performance and having an electron blocking ability, a highly stable thin-film state, and excellent heat resistance is provided as material for an organic electroluminescent device of high efficiency and high durability, and the organic electroluminescent device of high efficiency and high durability is provided using this compound. The compound of a general formula (Chemical Formula 1) having a substituted acridan ring structure is used as a constituent material of at least one organic layer in the organic electroluminescent device that includes a pair of electrodes and one or more organic layers sandwiched between the pair of electrodes. ##STR00001##