Abstract: A method for the preparation of a cohesive non-porous perovskite layer on a substrate (104) comprising: forming a thin film of a solution containing a perovskite material dissolved in a solvent onto the substrate to form a liquid film (104) of the solution on the substrate, applying a crystallisation agent (112) to a surface of the film to precipitate perovskite crystals from the 5 solution to form the cohesive non-porous perovskite layer (116) on the substrate.

Abstract: A photovoltaic device including cathode and anode electrodes (3, 11), and a photovoltaically active layer (5) located over both said electrodes.

Abstract: A sensor element (1, 20, 21, 22) capable of sensing more than one spectral band of electromagnetic radiation with the same (x-y) spatial location, especially where the dimensions x-y-z form a set of Cartesian coordinates with z parallel to the direction of incident electromagnetic radiation, is characterized in that the element consists of a stack of sub-elements (3, 5, 7) each capable of sensing different spectral bands of electromagnetic radiation. These sub-elements (3, 5, 7) each contain a non-silicon semiconductor where the non-silicon semiconductor in each sub-element (3, 5, 7) is sensitive to and/or has been sensitized to be sensitive to different spectral bands of electromagnetic radiation.

Abstract: The invention concerns an electrochromic device comprising a single supporting substrate (1) on which are disposed a working electrode (6) which is electrochromic per se and/or bears an electrochromic material on at least a portion thereof; a counter electrode (3); and a layer of an electrically insulating material (4) separating the electrodes; wherein said electrochromic material has a major surface at least a portion of which forms at least a portion of an external surface of the device. The new device allows deposition of electrochromic coatings on a variety of substrates which need not be transparent.

Abstract: The invention concerns discrete electrochromic particles comprising conducting, semiconducting or insulating nanoparticles having one or more electrochromic compounds adsorbed on the surface thereof. These particles may be deposited on an electrode in a single process step at a relatively low temperature, thereby allowing the use of heat-sensitive materials such as plastics as flexible substrates for the electrode.

Abstract: The invention concerns an electrochromic device comprising a single supporting substrate (1) on which are disposed a working electrode (6) which is electrochromic per se and/or bears an electrochromic material on at least a portion thereof; a counter electrode (3); and a layer of an electrically insulating material (4) separating the electrodes; wherein said electrochromic material has a major surface at least a portion of which forms at least a portion of an external surface of the device. The new device allows deposition of electrochromic coatings on a variety of substrates which need not be transparent.

Abstract: The invention concerns discrete electrochromic particles comprising conducting, semiconducting or insulating nanoparticles having one or more electrochromic compounds adsorbed on the surface thereof. These particles may be deposited on an electrode in a single process step at a relatively low temperature, thereby allowing the use of heat-sensitive materials such as plastics as flexible substrates for the electrode.

Abstract: A solid state p-n heterojunction comprising an electron conductor and a hole conductor; it further comprises a sensitising semiconductor, said sensitizing semiconductor being located at an interface between said electron conductor and said hole conductor. In particular, the sensitizing semiconductor is in form of quantum-dots. A solid state sensitized photovoltaic cell comprises such a heterojunction between two electrodes.

Abstract: A solid state p-n heterojunction comprising an electron conductor and a hole conductor; it further comprises a sensitising semiconductor, said sensitizing semiconductor being located at an interface between said electron conductor and said hole conductor. In particular, the sensitizing semiconductor is in form of quantum-dots. A solid state sensitized photovoltaic cell comprises such a layered heterojunction between two electrodes.

Abstract: A solid state p-n heterojunction comprising an electron conductor and a hole conductor; it further comprises a sensitising semiconductor, said sensitizing semiconductor being located at an interface between said electron conductor and said hole conductor. In particular, the sensitizing semiconductor is in form of quantum-dots. A solid state sensitized photovoltaic cell comprises such a heterojunction between two electrodes.

Abstract: A solid state p-n heterojunction comprising an electron conductor and a hole conductor; it further comprises a sensitising semiconductor, said sensitizing semiconductor being located at an interface between said electron conductor and said hole conductor. In particular, the sensitizing semiconductor is in form of quantum-dots. A solid state sensitized photovoltaic cell comprises such a layered heterojunction between two electrodes.

Abstract: A photovoltaic cell comprising an electrolyte which comprises a hole conductor compound as redox system.