Abstract: The present disclosure relates to devices that include a perovskite, where, when a first condition is met, at least a portion of the perovskite is in a first phase that substantially transmits light, when a second condition is met, at least a portion of the perovskite is in a second phase that substantially absorbs light, and the perovskite is reversibly switchable between the first phase and the second phase by reversibly switching between the first condition and the second condition.

Abstract: The present disclosure relates to a device that includes a perovskite layer; and a first layer that includes a molecule having a structure according to formula (I) Wherein the perovskite layer and the first layer are in physical contact, n is between 1 and 10, inclusively, R1 includes at least one of hydrogen, a first alkyl group, a first alkoxy group, and/or a first halogen, R2 includes at least one of hydrogen, a second alkyl group, a second alkoxy group, and/or a second halogen, R1 is bonded to aromatic ring (A) at carbon atom (1), carbon atom (2), carbon atom (3), or carbon atom (4), R2 is bonded to aromatic ring (B) at carbon atom (5), carbon atom (6), carbon atom (7), or carbon atom (8), and R1 and R2 are the same or different.

Abstract: Compositions comprise a perovskite and a non-perovskite. Perovskites comprise AxA?yA?(1?x?y)BX3, and non-perovskites may comprise A?, B and X, where A is a first cation, A? is a second cation, A? is a third cation, B is a fourth cation, X is an anion. In some instances, A, A?, and A? are each independently (NH2)2CH+, CH3NH3+, Cs+, Rb+, or (NH2)2(C?NH2)+, with the proviso that A, A?, and A? are each different. The perovskite may have a first crystal structure in which the anion is corner-sharing, the non-perovskite may have a second crystal structure comprising at least one of an orthorhombic structure, a hexagonal structure, or a perovskite-like structure, and 1?x?y may be greater than about 0.15.

Abstract: Described herein are spin polarized light emitting diodes (LEDs) and methods of making the same. Spin polarization is achieved via chiral induced spin selectivity where, for example, a stereochemically active cation is included in a perovskite to form the conductive layer of an LED device. Advantageously, the devices and methods described herein allow for spin polarization at room temperature and without application of a magnetic field or ferromagnetic contacts, in contrast to other described spin selective LEDs.

Abstract: The present disclosure relates to a composition that includes a nanocrystalline core that includes a perovskite and having an outer surface, and a chiral molecule having a functional group, where the functional group is bonded to a first portion of the outer surface, and the composition is capable of circularly polarized luminescence (CPL). In some embodiments of the present disclosure, the composition is capable of absorbing circularly-polarized light.

Abstract: The present disclosure relates to devices that include a perovskite, where, when a first condition is met, at least a portion of the perovskite is in a first phase that substantially transmits light, when a second condition is met, at least a portion of the perovskite is in a second phase that substantially absorbs light, and the perovskite is reversibly switchable between the first phase and the second phase by reversibly switching between the first condition and the second condition.

Abstract: The present disclosure relates to a perovskite that includes A1-xA?xBX3, where A is a first cation, A? is a second cation, B is a third cation, X is a first anion, and 0<1?x?1. In some embodiments of the present disclosure, the perovskite may further include a second anion (X?) such that the perovskite includes A1-xA?xB(X1-zX?z)3, where 0<z?1. In some embodiments of the present disclosure, the perovskite may further include a fourth cation (A*) such that the perovskite includes A1-x-yA?xA*yB(X1-zX?z)3, where 0<y?1. In some embodiments of the present disclosure, the perovskite may further include a fifth cation (B?) such that the perovskite includes A1-x-yA?xA*yB1-aB?a(X1-zX?z)3, where 0<a?1.

Abstract: The present disclosure relates to devices that include a perovskite, where, when a first condition is met, at least a portion of the perovskite is in a first phase that substantially transmits light, when a second condition is met, at least a portion of the perovskite is in a second phase that substantially absorbs light, and the perovskite is reversibly switchable between the first phase and the second phase by reversibly switching between the first condition and the second condition.

Abstract: An aspect of the present disclosures is a method that includes applying a perovskite precursor solution to a first solid conductor and treating the perovskite precursor solution such that a first portion of the perovskite precursor solution is converted to a first solid perovskite, where the first solid conductor comprises a first charge transport characteristic, which is predominantly p-type or predominantly n-type, and the treating results in the first solid perovskite having a second charge transport characteristic that is substantially the same as the first charge transport characteristic.

Abstract: The present disclosure relates to a perovskite that includes A1-xA?xBX3, where A is a first cation, A? is a second cation, B is a third cation, X is a first anion, and 0<x?1. In some embodiments of the present disclosure, the perovskite may further include a second anion (X?) such that the perovskite includes A1-xA?xB(X1-zX?z)3, where 0<z?1. In some embodiments of the present disclosure, the perovskite may further include a fourth cation (A*) such that the perovskite includes A1-x-yA?xA*yB(X1-zX?z)3, where 0<y?1. In some embodiments of the present disclosure, the perovskite may further include a fifth cation (B?) such that the perovskite includes A1-x-yA?xA*yB1-aB?a(X1-zX?z)3, where 0<a?1.

Abstract: The present disclosure relates to a composition that includes a particle and a surface species, where the particle has a characteristic length between greater than zero nm and 100 nm inclusively, and the surface species is associated with a surface of the particle such that the particle maintains a crystalline form when the composition is at a temperature between ?180° C. and 150° C.

Abstract: An aspect of the present disclosures is a method that includes applying a perovskite precursor solution to a first solid conductor and treating the perovskite precursor solution such that a first portion of the perovskite precursor solution is converted to a first solid perovskite, where the first solid conductor comprises a first charge transport characteristic, which is predominantly p-type or predominantly n-type, and the treating results in the first solid perovskite having a second charge transport characteristic that is substantially the same as the first charge transport characteristic.

Abstract: The present disclosure relates to devices that include a perovskite, where, when a first condition is met, at least a portion of the perovskite is in a first phase that substantially transmits light, when a second condition is met, at least a portion of the perovskite is in a second phase that substantially absorbs light, and the perovskite is reversibly switchable between the first phase and the second phase by reversibly switching between the first condition and the second condition.

Abstract: The present disclosure relates to a composition that includes a particle and a surface species, where the particle has a characteristic length between greater than zero nm and 100 nm inclusively, and the surface species is associated with a surface of the particle such that the particle maintains a crystalline form when the composition is at a temperature between ?180° C. and 150° C.