Sulfur-fused perylene diimides (PDIs) having the formula 2PDI-nS, wherein n is an integer. Such sulfur-fused PDIs (e.g., 2PDI-2S, 2PDI-3S, and 2PDI-4S) are incorporated as electron acceptors in an active region of a bulk heterojunction solar cell and/or as an electron transport layer. Example solar cells exhibit a power conversion efficiency above 5% and a fill factor above 70% (a record high for non-fullerene bulk heterojunction solar cell devices) when 2PDI-nS is used as the electron acceptor. In addition, the solar cells exhibit low open circuit voltage (V.sub.oc) loss.

An aromatic amine derivative represented by the following formula (1) wherein at least one of Ar.sub.1 to Ar.sub.4 is a heterocyclic group represented by the following formula (2) wherein X.sub.1 is an oxygen atom or a sulfur atom. ##STR00001##

An imaging element which is formed by sequentially stacking at least an anode, an anode-side buffer layer, a photoelectric conversion layer, and a cathode, in which the anode-side buffer layer includes a material having structural formula

##STR00001##

in which thiophene and carbazole are combined.

The present invention describes dibenzofuran derivatives substituted by electron-deficient heteroaryl groups, and electronic devices, especially organic electroluminescent devices, comprising these compounds as triplet matrix materials.

The present teachings relate to an organic electroluminescent transistor with improved light-emission characteristics. More specifically, the present organic electroluminescent transistor has an emissive ambipolar channel including at least one layer of an n-type semiconductor material, at least one layer of a p-type semiconductor material, and at least one layer of an emissive material arranged between the layers of the p-type and n-type semiconductor materials, with the n-type semiconductor material comprising an electron-transporting compound represented by formula (N-1):

##STR00001##

where X, Ar, Ar′, R.sup.1, R.sup.2, m and m′ are as defined herein.

Embodiments include radiative heat-blocking materials comprising one or more non-fullerene components and optionally one or more hole-scavenging components. Embodiments further include windows comprising a transparent photovoltaic device configured to transmit visible light and absorb infrared radiation, wherein an active layer of the photovoltaic device comprises the radiative heat-blocking material. Embodiments further include other devices based on the radiative heat-blocking materials.

An OLED multilayer electroluminescent device includes a cathode, an anode, a light-emitting layer (LEL) disposed therebetween, and charge-transporting layers disposed between (A) the cathode and the light-emitting layer, (B) the anode and the light-emitting layer, or (C) both (A) and (B). The light-emitting layer (LEL) includes a host material and an emitter. The host material includes a high-entropy non-crystallizable molecular glass mixture, which includes hole-transporting capabilities, electron-transporting capabilities, or ambipolar capabilities. The ambipolar capabilities include hole-transporting capabilities and electron-transporting capabilities.

An object to be achieved by the present invention is to provide an organic semiconductor element and an organic semiconductor film having high mobility and excellent heat resistance, and a manufacturing method thereof, to provide a novel compound that is suitable as an organic semiconductor, and to provide a composition for forming an organic semiconductor film in which coating film formability is excellent, with which an organic semiconductor element that has high mobility can be obtained, and in which heat resistance is excellent, an organic semiconductor element in which the composition for forming an organic semiconductor film is used, and a manufacturing method thereof.

The organic semiconductor element according to the present invention includes a compound represented by Formula 1 below included in an organic semiconductor layer.

##STR00001##

A compound represented by formula (1):

##STR00001##

wherein R.sup.1 to R.sup.4, a to d, L.sup.0 to L.sup.2, and Ar are as defined in the description, is a material providing an organic electroluminescence device which can be operated at a low driving voltage and has a long lifetime.

An imaging device includes at least one unit pixel cell including a photoelectric converter and a voltage application circuit. The photoelectric converter includes a first electrode, a light-transmitting second electrode, a first photoelectric conversion layer containing a first material and a second photoelectric conversion layer containing a second material. The impedance of the first photoelectric conversion layer is larger than the impedance of the second photoelectric conversion layer. The voltage application circuit applies a first voltage or a second voltage having a larger absolute value than the first voltage selectively between the first electrode and the second electrode.