The invention relates to novel polymers containing repeating units based on benzo[2,1,3]thiadiazole-5,6-dicarboxylic acid bis-ester, monomers and methods for their preparation, their use as semiconductors in organic electronic (OE) devices, especially in organic photovoltaic (OPV) devices, and to OE and OPV devices comprising these polymers.

Design and use of photo-switching, fullerene-based dyads of the design x-D-y-A or D-y-A-x as interfacial layers (IFL) for organic photovoltaic (OPV) devices are described herein. The fullerene-based dyads and triads of the present invention contain electron-donating substituents such as porphyrins or phthalocyanines that exhibit charge separation states with long lifetimes upon irradiation, resulting in rejection of electrons reaching the electrode and concurrently promoting the conduction of holes. This phenomenon has a strong rectifying effect on the whole device, not just the interfaces, resulting in improved charge extraction from the interior of the photo-active layer. The invention further describes anchoring an IFL to the ITO surface as a monolayer, bilayer, or greater multilayers. One OPV design embodiment of the present invention embodiment involves the formation of covalent bonds via silane groups (—SiR.sub.3) as the anchor (x), to form siloxane bonds.

Provided are an organic-inorganic hybrid perovskite nanocrystal particle light emitting body having a gradient structure, a method of producing the same, and a light emitting element using the same. The organic-inorganic hybrid perovskite nanocrystal particle light emitting body having a gradient structure includes an organic-inorganic hybrid perovskite nanocrystal which is dispersible in an organic solvent, wherein the nanocrystal has a gradient composition in which a composition is changed from the center thereof to the outside. Therefore, the gradual change in the content in the nanocrystal may be used to uniformly adjust a fraction in the nanocrystal, to reduce surface oxidation, and to improve exciton confinement in the perovskite present in large quantities inside the nanocrystal, and thus light emission efficiency may be improved and durability and stability may be increased.

A polybenzodifuran ladder polymer is disclosed.

An organic photovoltaic device comprising a polymer: ##STR00001##
and an acceptor. In this organic photovoltaic device, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently selected from the group consisting of: a halogen, a substituted alkyl, an unsubstituted alkyl, a substituted aryl, an unsubstituted aryl, a substituted heteroaryl and an unsubstituted heteroaryl.

Disclosed are conjugated polymers having desirable properties as semiconducting materials. Such polymers are cheap and easy to synthesize, and can exhibit good solubility and great solution processibility, and that enable highly efficient OPVs.

Provided are a photoelectric conversion element including a first electrode having a photosensitive layer including a light absorber on a conductive support and a second electrode facing the first electrode, in which the light absorber includes a compound having a perovskite-type crystal structure including organic cations, cations of a metallic atom other than elements belonging to Group I of the periodic table, and anions, and at least some of the organic cations constituting the compound are organic cations having a silyl group and a solar cell using the photoelectric conversion element.

Also provided is a composition containing a compound represented by Formula (1a) and a halogenated metal.

R.sup.1.sub.3Si-L-NR.sup.2.sub.3Hal  Formula (1a)

In the formula, R.sup.1, R.sup.2, and L are specific groups. Hal represents a halogen atom.

A radiation detector includes a first detecting part including a first organic detection layer and a first layer, and a second detecting part including a second organic detection layer. The first layer includes a first material and a first thickness. The second detecting part does not include the first layer. The second detecting part does not include a second layer, or the second detecting part includes the second layer that includes at least one of a second material or a second thickness. The second material is different from the first material. The second thickness is different from the first thickness. The first material includes at least one of a first organic material or a first element. The second material includes at least one of a second organic material or a second element.

The present invention provides a light-transmitting electrode which has high electrical conductivity and high electron blocking performance. The present invention also provides a solar cell which is capable of achieving high energy conversion efficiency at low cost. The present invention provides a method for producing a light-transmitting electrode that has a light-transmitting substrate, a carbon nanotube film which is formed directly or indirectly on the light-transmitting substrate, and a metal oxide film which is formed directly on the carbon nanotube film. This production method includes vapor depositing the metal oxide film, which contains oxygen and a metal element belonging to the group 4, 5 or 6 of the periodic table, on one surface or both surfaces of the carbon nanotube film. The present invention provides a light-transmitting electrode which includes a light-transmitting substrate and a conductive carbon nanotube film that is formed directly or indirectly on the light-transmitting substrate.

The invention relates to a formulation comprising p-type and n-type organic semiconductors (OSC) and one or more organic solvents, its use for the preparation of organic electronic (OE) devices, especially for bulk heterojunction (BHJ) organic photovoltaic (OPV) devices, to a process for preparing an OE device, especially a BHJ OPV device, using the formulation, and an OE device, especially a BHJ OPV device, prepared using such a process or formulation.