A synchronized piezoelectric and luminescence (SPL) material includes a core layer including light-emitting particles and a shell layer which is attached onto a surface of the core layer and includes ligands having a piezoelectric property. Therefore, a piezoelectric property and a luminescent property can be simultaneously implemented using a single SPL material in which piezoelectric ligands and light-emitting particles are chemically coupled.

Bandgap-tunable perovskite compositions are provided having the formula CsPb(A.sub.xB.sub.y).sub.3, wherein A and B are each a halogen. The mixed halide perovskite composition has a morphology which suppresses phase segregation to stabilize a tuned bandgap of the mixed halide perovskite composition. For example, the perovskite may be in the form of nanocrystals embedded in a non-perovskite matrix, which, for example, may have the formula Cs.sub.4Pb(A.sub.xB.sub.y).sub.6, wherein A and B are each a halogen. Solar cells and light-emitting diodes comprising the mixed perovskite compositions are also provided.

Bandgap-tunable perovskite compositions are provided having the formula CsPb(A.sub.xB.sub.y).sub.3, wherein A and B are each a halogen. The mixed halide perovskite composition has a morphology which suppresses phase segregation to stabilize a tuned bandgap of the mixed halide perovskite composition. For example, the perovskite may be in the form of nanocrystals embedded in a non-perovskite matrix, which, for example, may have the formula Cs.sub.4Pb(A.sub.xB.sub.y).sub.6, wherein A and B are each a halogen. Solar cells and light-emitting diodes comprising the mixed perovskite compositions are also provided.

The present disclosure relates to a perovskite sheet that includes two outer layers, each including A′X′; and a first layer that includes BX.sub.2, where B is a first cation, A′ is a second cation, X is a first anion, X′ is a second anion, and the first BX.sub.2 layer is positioned between the two outer layers.

The present disclosure relates to a perovskite sheet that includes two outer layers, each including A′X′; and a first layer that includes BX.sub.2, where B is a first cation, A′ is a second cation, X is a first anion, X′ is a second anion, and the first BX.sub.2 layer is positioned between the two outer layers.

The invention relates to metal complex compounds of the formula M.sub.k(L).sub.x(Y).sub.kz-nx, where the ligand L has the formula (I), and to metal complex compounds which include the reaction product of at least one salt or a complex of a transition metal or a main group metal element of the groups 13 to 15 and at least one 1,3-ketoamide. Such complex compounds are suitable in particular as catalysts for polyurethane compositions. The invention also relates to two-component polyurethane compositions including at least one polyisocyanate as the first component, at least one polyol as the second component, and at least one such metal complex compound as the catalyst. The invention additionally relates to different uses of the two-component polyurethane compositions.

The invention relates to metal complex compounds of the formula M.sub.k(L).sub.x(Y).sub.kz-nx, where the ligand L has the formula (I), and to metal complex compounds which include the reaction product of at least one salt or a complex of a transition metal or a main group metal element of the groups 13 to 15 and at least one 1,3-ketoamide. Such complex compounds are suitable in particular as catalysts for polyurethane compositions. The invention also relates to two-component polyurethane compositions including at least one polyisocyanate as the first component, at least one polyol as the second component, and at least one such metal complex compound as the catalyst. The invention additionally relates to different uses of the two-component polyurethane compositions.

A system and method for fabricating a perovskite film is provided, the system including a substrate stage configured to rotate around its central axis at a rotation speed, a first set of evaporation units, each coupled to the side section or the bottom section of the chamber, a second set of evaporation units coupled to the bottom section, and a shield defining two or more zones having respective horizontal cross-sectional areas, which are open and facing the substrate, designated for the two or more evaporation units in the second set. The resultant perovskite film includes multiple unit layers, wherein each unit layer is formed by one rotation of the substrate stage, and the composition and thickness of the unit layer are controlled by adjusting at least the evaporation rates, the rotation speed and the horizontal cross-sectional areas.

The hybrid organic-inorganic perovskite-based solar cell with copper oxide as a hole transport material includes a transparent conducting film layer (12) sandwiched between a glass substrate (11) and a titanium dioxide layer (14). The transparent conducting film layer (12) can be fluorine-doped tin oxide. A lead methylammonium tri-iodide perovskite layer (16) is formed on the titanium dioxide layer (14), such that the titanium dioxide layer (14) is sandwiched between the lead methylammonium tri-iodide perovskite layer (16) and the transparent conducting film layer (12). A layer of copper oxide (Cu2O) (18), as a hole transport material, is formed on the lead methylammonium tri-iodide perovskite layer (16). The lead methylammonium tri-iodide perovskite layer (16) is sandwiched between the layer of hole transport material (18) and the titanium dioxide layer (14). A gold contact (20) is formed on the layer of hole transport material (18).

The hybrid organic-inorganic perovskite-based solar cell with copper oxide as a hole transport material includes a transparent conducting film layer (12) sandwiched between a glass substrate (11) and a titanium dioxide layer (14). The transparent conducting film layer (12) can be fluorine-doped tin oxide. A lead methylammonium tri-iodide perovskite layer (16) is formed on the titanium dioxide layer (14), such that the titanium dioxide layer (14) is sandwiched between the lead methylammonium tri-iodide perovskite layer (16) and the transparent conducting film layer (12). A layer of copper oxide (Cu2O) (18), as a hole transport material, is formed on the lead methylammonium tri-iodide perovskite layer (16). The lead methylammonium tri-iodide perovskite layer (16) is sandwiched between the layer of hole transport material (18) and the titanium dioxide layer (14). A gold contact (20) is formed on the layer of hole transport material (18).