Hole transporting material obtained through a process comprising: reacting at least one heteropoly acid containing at least one transition metal belonging to group 5 or 6 of the Periodic Table of the Elements; with an equivalent amount of at least one salt or one complex of a transition metal belonging to group 5 or 6 of the Periodic Table of the Elements with an organic anion, or with an organic ligand;
in the presence of at least one organic solvent selected from alcohols, ketones, esters. Said hole transporting material can be advantageously used in the construction of photovoltaic devices (or solar devices) such as, for example, photovoltaic cells (or solar cells), photovoltaic modules (or solar modules), either on a rigid support, or on a flexible support. Furthermore, said hole transporting material can be advantageously used in the construction of Organic Light Emitting Diodes (OLEDs), or of Organic Field Effect Transistors (OFETs). In particular, said hole transporting material can be advantageously used in the construction of a polymer photovoltaic cell (or solar cell) with an inverted structure.

The present invention aims to provide a solar cell in which a decrease in photoelectric conversion efficiency due to continuous exposure to light (photodegradation) is reduced, and a method of producing the solar cell. The present invention relates to a solar cell, including: an electrode; a counter electrode; and a photoelectric conversion layer between the electrode and the counter electrode, the photoelectric conversion layer containing an organic-inorganic perovskite compound represented by the formula R-M-X.sub.3 where R is an organic molecule, M is a metal atom, and X is a halogen atom or a chalcogen atom, the solar cell satisfying the formula (1):
N(T,I)/N(0,I)<5  (1)
where N(0, I) is a carrier density of the organic-inorganic perovskite compound immediately after start of exposure of the solar cell to light at an intensity of I mW/cm.sup.2, and N(T, I) is the carrier density of the organic-inorganic perovskite compound after continuous exposure of the solar cell to light at an intensity of I mW/cm.sup.2 for T hour/hours.

The invention relates to a method for synthesis of films made of light-absorbing material with perovskite-like structure which can be used for fabrication of perovskite solar cells. The method for synthesis of films made of light-absorbing material with perovskite-like structure with a structural formula ACB.sub.3 is characterized by sequential deposition of a layer of a reagent C onto a layer of a reagent AB with a thickness determined by stoichiometry of the reaction followed by the immersion of the layers in a liquid or gaseous medium containing reagent B.sub.2 where component A states for CH.sub.3NH.sub.3.sup.+, (NH.sub.2).sub.2CH.sup.+, C(NH.sub.2).sub.3.sup.+, Cs.sup.+ or a mixture thereof, component B states for Cl.sup.−, Br.sup.−, I.sup.− or a mixture thereof, component C states for metals Sn, Pb, Bi, or their melts, oxides, salts. The technical result achieved using the claimed invention is a simple and fast method for fabrication of a layer of light-absorbing organic-inorganic material with a perovskite-like structure which is homogeneous due to the formation of a film of the intermediate phase AB-B.sub.2 with improved morphology on the surfaces of a large area due to rapid crystallization, which allows the obtained material to be used in solar cells of large area.

A semiconductor device includes a substrate, a first electrode located on the substrate, a metal halide perovskite layer located on the first electrode, a second electrode located on the metal halide perovskite layer, and passivation molecules that passivate the metal halide perovskite layer. The metal halide perovskite layer has (1) a top surface defect located in a top surface and (2) an inter-grain defect located at an interface between two adjacent grains, and the passivation molecules passivate at least one of the top surface defect and the inter-grain defect.

A semiconductor device includes a substrate, a first electrode located on the substrate, a metal halide perovskite layer located on the first electrode, a second electrode located on the metal halide perovskite layer, and passivation molecules that passivate the metal halide perovskite layer. The metal halide perovskite layer has (1) a top surface defect located in a top surface and (2) an inter-grain defect located at an interface between two adjacent grains, and the passivation molecules passivate at least one of the top surface defect and the inter-grain defect.

A perovskite solar cell includes a transparent electrode, an electron transport layer, a perovskite layer, a hole transport layer, and a second electrode in sequence. The perovskite layer includes a main perovskite layer and a two-dimensional perovskite coating layer covering both surface and periphery of the main perovskite layer. The two-dimensional perovskite coating layer includes a first overlay layer disposed between the main perovskite layer and the electron transport layer, a second overlay layer disposed between the main perovskite layer and the hole transport layer, and a third overlay layer covering the periphery of the main perovskite layer.

A perovskite solar cell includes a transparent electrode, an electron transport layer, a perovskite layer, a hole transport layer, and a second electrode in sequence. The perovskite layer includes a main perovskite layer and a two-dimensional perovskite coating layer covering both surface and periphery of the main perovskite layer. The two-dimensional perovskite coating layer includes a first overlay layer disposed between the main perovskite layer and the electron transport layer, a second overlay layer disposed between the main perovskite layer and the hole transport layer, and a third overlay layer covering the periphery of the main perovskite layer.

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 present disclosure provides a laser-annealing method for fabricating large-grain perovskite films for perovskite solar cells based on optimal conditions including laser wavelength, scanning speed and laser power. Compared with the conventional technology, the present laser-annealing method provides the laser-annealed perovskite films with better crystallinity and larger grains thereby improving the photovoltaic performance of the perovskite solar cells.

A charge transport varnish containing a charge transport substance, an electron-accepting dopant substance, and an organic solvent, wherein the electron-accepting dopant substance contains one or more types selected from naphthalene disulfonic acid, naphthalene trisulfonic acid, and naphthalene tetrasulfonic acid. This charge transport varnish is suitable for forming a hole collection layer that can be used to produce an organic photoelectric conversion element which exhibits high photoelectric conversion efficiency.