Abstract: The invention provides an optoelectronic device comprising a photoactive region, which photoactive region comprises: an n-type region comprising at least one n-type layer; a p-type region comprising at least one p-type layer; and, disposed between the n-type region and the p-type region: a layer of a perovskite semiconductor without open porosity. The perovskite semiconductor is generally light-absorbing. In some embodiments, disposed between the n-type region and the p-type region is: (i) a first layer which comprises a scaffold material, which is typically porous, and a perovskite semiconductor, which is typically disposed in pores of the scaffold material; and (ii) a capping layer disposed on said first layer, which capping layer is said layer of a perovskite semiconductor without open porosity, wherein the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer.

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 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: Methods and compositions for plastid transformation and regeneration or development of transplastomic plants are provided. Embryo explants may be excised from seeds, and their meristematic tissue may be transformed directly without initiation of any callus phase before and/or after transformation. The present methods may be performed with fewer culturing steps relative to conventional methods, thereby enabling more rapid and efficient production of targeted transplastomic events in plants.

Abstract: The invention provides a process for producing a layer of a semiconductor material, wherein the process comprises: a) disposing on a substrate: i) a plurality of particles of a semiconductor material, ii) a binder, wherein the binder is a molecular compound comprising at least one metal atom or metalloid atom, and iii) a solvent; and b) removing the solvent. The invention also provides a layer of semiconductor material obtainable by this process. In a preferred embodiment, the particles of a semiconductor material comprise mesoporous particles of the semiconductor material or mesoporous single crystals of the semiconductor material.

Abstract: The invention provides an optoelectronic device comprising a photoactive region, which photoactive region comprises: an n-type region comprising at least one n-type layer; a p-type region comprising at least one p-type layer; and, disposed between the n-type region and the p-type region: a layer of a perovskite semiconductor without open porosity. The perovskite semiconductor is generally light-absorbing. In some embodiments, disposed between the n-type region and the p-type region is: (i) a first layer which comprises a scaffold material, which is typically porous, and a perovskite semiconductor, which is typically disposed in pores of the scaffold material; and (ii) a capping layer disposed on said first layer, which capping layer is said layer of a perovskite semiconductor without open porosity, wherein the perovskite semiconductor in the capping layer is in contact with the perovskite semiconductor in the first layer.