Abstract: A photovoltaic device comprises plural layers separated into plural cells, each comprising a region of a photoactive layer and electrodes on opposite sides thereof. Each of the regions of the photoactive layer are formed comprising a first part that comprises photoactive material and a second part that is not photoactive and that has a greater transmittance of visible light than the light absorbing photoactive material, in pre-selected locations, or in a pre-selected distribution of locations, across the region of the photoactive layer. One of the first and second parts are located in plural separate areas within the other of the first and second parts. The transparency of the photovoltaic device is increased by the transmission of light through the second part that is not photoactive.

Abstract: There is provided a method of producing a photovoltaic device comprising a photoactive region comprising a layer of perovskite material, wherein the layer of perovskite material is disposed on a surface that has a roughness average (Ra) or root mean square roughness (Rrms) of greater than or equal to 50 nm. The method comprises using vapour deposition to deposit a substantially continuous and conformal solid layer comprising one or more initial precursor compounds of the perovskite material, and subsequently treating the solid layer with one or more further precursor compounds to form a substantially continuous and conformal solid layer of the perovskite material on the rough surface. There is also provided a photovoltaic device comprising a photoactive region comprising a layer of perovskite material disposed using the method.

Abstract: The present invention provides a method of forming a crystalline or polycrystalline layer of an organic-inorganic metal halide perovskite material comprising a three-dimensional crystal structure represented by the formula AMX3, in which A represents an organic cation or a mixture of two or more different cations, at least one of which is an organic cation, M represents a divalent metal cation or a mixture of two or more different divalent metal cations, and X represents halide anions which are the same or different, the method comprising the steps of: (i) forming a first layer on the surface of a substrate, the first layer comprising an organic-inorganic metal halide perovskite material having a planar, layered two-dimensional crystal structure (ii) reacting the first layer with one or more organic halides to form the crystalline or polycrystalline layer comprising an organic-inorganic metal halide perovskite material having the formula AMX3.

Abstract: There is provided a multi junction photovoltaic device comprising a first sub-cell comprising a photoactive region comprising a layer of perovskite material, a second sub-cell comprising a photoactive silicon absorber. and an intermediate region disposed between and connecting the first sub-cell and the second sub-cell. The intermediate region comprises an interconnect layer, the interconnect layer comprising a two-phase material comprising elongate (i.e. filament like) silicon nanocrystals embedded in a silicon oxide matrix.

Abstract: There is provided a photovoltaic device that comprises a photoactive region, the photoactive region comprising a perovskite material of general formula A1-xA?xBX3-yX?y, wherein A is a formamidinium cation (HC(NH)2)2+), A? is a caesium cation (Cs+) B is at least one divalent inorganic cation, X is iodide and X is bromide, and x is greater than 0 and equal to or less than 0.4 and y is greater than 0 and less than or equal to 3. There is also provided a method of producing a photovoltaic device comprising a photoactive region comprising the perovskite material, and formulations for use in the formation of the perovskite material.

Abstract: A formulation for use in the preferential formation of thin films of a perovskite material AMX3 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 metal cations M; one or more second cations A?; one or more first anions X and one or more second anions X?.

Abstract: There is provided a method of encapsulating a photovoltaic module comprising a plurality of photovoltaic devices. The method comprises forming a wall of compact glass that extends from a periphery of a surface of a first glass sheet to a periphery of an opposing surface of a second glass sheet, the plurality of photovoltaic devices being located within a volume enclosed by the first glass, the second glass sheet and the wall of compact glass, wherein the wall of compact glass is formed from a plurality of courses of glass frit, and sealing the enclosed volume using laser-assisted glass frit bonding.

Abstract: There is provided a photovoltaic device that comprises a photoactive region, the photoactive region comprising a perovskite material of general formula A1?xA?xBX3?yX?y wherein A is a formamidinium cation ((HC(NH2)2)+), A? is a caesium cation (Cs+), B is at least one divalent inorganic cation, X is iodide and X? is bromide, and x is greater than 0 and equal to or less than 0.4 and y is greater than 0 and less than or equal to 3. There is also provided a method of producing a photovoltaic device comprising a photoactive region comprising the perovskite material, and formulations for use in the formation of the perovskite material.

Abstract: 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?.

Abstract: A photovoltaic device comprises plural layers separated into plural cells, each comprising a region of a photoactive layer and electrodes on opposite sides thereof. Each of the regions of the photoactive layer are formed comprising a first part that comprises photoactive material and a second part that is not photoactive and that has a greater transmittance of visible light than the light absorbing photoactive material, in pre-selected locations, or in a pre-selected distribution of locations, across the region of the photoactive layer. One of the first and second parts are located in plural separate areas within the other of the first and second parts. The transparency of the photovoltaic device is increased by the transmission of light through the second part that is not photoactive.

Abstract: An optoelectronic device has a layered construction, comprising a base layer, a first conductive layer, a photoactive layer and a second conductive layer. Plural separation channels extending through the photoactive layer and the first conductive layer separate the photoactive layer into photoactive regions, and insulator material extends through the respective separation channels to the base layer. Between adjacent photoactive regions, electrical connectors extend inside the lateral extent of the insulator material between a surface of a second electrode that is in electrical contact with one photoactive region to an opposing surface of a first electrode that is in electrical contact with the other photoactive region. By forming the electrical connectors extend inside the lateral extent of the insulator material, the overall size of the connection is minimized.

Abstract: There is provided a photovoltaic device that comprises a front electrode, a back electrode, and disposed between the front electrode and the back electrode, an electron transporter region comprising an electron transporter layer; a hole transporter region comprising a hole transporter layer, and a layer of perovskite semiconductor disposed between and in contact with the electron transporter layer and the hole transporter layer. The electron transporter region is nearest to the front electrode and the hole transporter region is nearest to the back electrode, and the electron transporter layer comprises any of a chalcogenide material and an organic material and has a thickness of at least 2 nm.

Abstract: A photovoltaic device comprises plural layers separated into plural cells, each comprising a region of a photoactive layer and electrodes on opposite sides thereof. Each of the regions of the photoactive layer are formed comprising a first part that comprises photoactive material and a second part that is not photoactive and that has a greater transmittance of visible light than the light absorbing photoactive material, in pre-selected locations, or in a pre-selected distribution of locations, across the region of the photoactive layer. One of the first and second parts are located in plural separate areas within the other of the first and second parts. The transparency of the photovoltaic device is increased by the transmission of light through the second part that is not photoactive.

Abstract: An optoelectronic device has a layered construction, comprising a base layer, a first conductive layer, a photoactive layer and a second conductive layer. Plural separation channels extending through the photoactive layer and the first conductive layer separate the photoactive layer into photoactive regions, and insulator material extends through the respective separation channels to the base layer. Between adjacent photoactive regions, electrical connectors extend inside the lateral extent of the insulator material between a surface of a second electrode that is in electrical contact with one photoactive region to an opposing surface of a first electrode that is in electrical contact with the other photoactive region. By forming the electrical connectors extend inside the lateral extent of the insulator material, the overall size of the connection is minimised.