Composite materials that include a polymer matrix and a metal halide perovskite. The metal halide perovskite may be a lead-free metal halide double perovskite. Devices that include a layer of a composite material, a first electrode, and a second electrode. Methods of forming composite materials and devices, including methods that include printing one or more layers with a 3D printer.

An organic semiconductor film according to an embodiment of the present disclosure includes an organic semiconductor material having a crystalline property, and the organic semiconductor film has carrier transportability and has three crystalline peaks in a range of a diffraction angle (2) of 15 or more and 30 or less in an XRD spectrum.

An organic semiconductor film according to an embodiment of the present disclosure includes an organic semiconductor material having a crystalline property, and the organic semiconductor film has carrier transportability and has three crystalline peaks in a range of a diffraction angle (2) of 15 or more and 30 or less in an XRD spectrum.

A photoelectric conversion element includes a pair of electrodes; an active layer provided between the pair of electrodes and including a p-type semiconductor (P); and a buffer layer provided between one of the pair of electrodes and the active layer and including a dielectric (D), in which the dielectric (D) has a band gap of 4 eV or more and a relative permittivity of 20 or more, and the photoelectric conversion element satisfies the following Expression (1).

[00001]$\begin{array}{cc}\mathrm{Ec}-E\left(L\right)>0.8\mathrm{eV}& \left(1\right)\end{array}$

In Expression (1), Ec represents an energy level at a lower end of a conduction band of the dielectric (D), and E(L) represents a LUMO energy level of the p-type semiconductor (P).

A photoelectric conversion element includes a pair of electrodes; an active layer provided between the pair of electrodes and including a p-type semiconductor (P); and a buffer layer provided between one of the pair of electrodes and the active layer and including a dielectric (D), in which the dielectric (D) has a band gap of 4 eV or more and a relative permittivity of 20 or more, and the photoelectric conversion element satisfies the following Expression (1).

[00001]$\begin{array}{cc}\mathrm{Ec}-E\left(L\right)>0.8\mathrm{eV}& \left(1\right)\end{array}$

In Expression (1), Ec represents an energy level at a lower end of a conduction band of the dielectric (D), and E(L) represents a LUMO energy level of the p-type semiconductor (P).

The driving voltage of a light-emitting device is lowered to improve the emission efficiency. The light-emitting device includes a first electrode, a second electrode, a light-emitting layer, and a first layer. The light-emitting layer is positioned between the first electrode and the second electrode. The first layer is positioned between the first electrode and the light-emitting layer. The light-emitting layer contains a light-emitting substance. The first layer contains a first organic compound. The HOMO level of the first organic compound is lower than or equal to 5.40 eV. The first organic compound provides a light-emitting device represented by General Formula (G1) below (Note that Q is O or S in General Formula (G1). One of A and B represents a group represented by General Formula (g1) above, and the other of A and B and R1 to R31 each independently represent any of H, D, an alkyl group, a cyclic saturated hydrocarbon group, an alkoxy group, a cyano group, halogen, a haloalkyl group, and an aromatic hydrocarbon group. Note that R9 and R10 may be bonded to each other to form a spirocyclic structure).

##STR00001##

The present invention provides a photoelectric conversion element having excellent quantum efficiency in a case of receiving blue light. In addition, the present invention provides an imaging element, an optical sensor, and a compound, which are related to the photoelectric conversion element. The photoelectric conversion element 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).

The present invention provides a photoelectric conversion element having excellent quantum efficiency in a case of receiving blue light. In addition, the present invention provides an imaging element, an optical sensor, and a compound, which are related to the photoelectric conversion element. The photoelectric conversion element 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).

Provided are a material that achieves higher sensitivity and higher resolution of a photoelectric conversion device for imaging, and a photoelectric conversion device for imaging using the above material. A material for a photoelectric conversion device for imaging, the material including an indolocarbazole compound represented by the following general formula (1) and a photoelectric conversion device for imaging using the above material. In the general formula (1), the ring B is fused with an adjacent ring at any position, and represents a six-membered ring represented by the formula (1B). The ring C is fused with an adjacent ring at any position, and represents a five-membered ring represented by the formula (1C). At least one of Ar.sup.1 to Ar.sup.5 is represented by the following general formula (2) or the like. In the general formula (2), * represents a bonding point to the general formula (1).

##STR00001##

The large-scale artificial synaptic device arrays based on the organic molecule-nanowire heterojunctions with tunable photoconductivity are proposed and demonstrated. The organic thin films of p-type 2,7-dioctyl[1]benzothieno[3,2-b][1] benzothiophene (C8-BTBT) or n-type phenyl-C61-butyric acid methyl ester (PC61BM) are used to wrap the InGaAs nanowire parallel arrays to configure two different type-I heterojunctions, respectively. Due to the difference in carrier injection, persistent negative photoconductivity (NPC) or positive photoconductivity (PPC) are achieved in these heterojunctions. The irradiation with different wavelengths (solar-blind to visible ranges) can stimulate the heterojunction devices, effectively mimicking the synaptic behaviors with two different photoconductivities. Evidently, these photosynaptic devices are illustrated with retina-like behaviors and capabilities for large-area integration, which reveals their promising potential for artificial visual systems.