A light valve containing ABX.sub.3 perovskite particles (200) suspended in a liquid suspension (300) that can control light transmittance is provided. The preferable ABX.sub.3 perovskite particles (200) are halide ABX.sub.3 perovskite particles wherein A is at least one of Cs.sup.+, CH.sub.3NH.sub.3.sup.+, and Rb.sup.+, B is at least one of Pb.sup.2+, Ge.sup.2+, and Sn.sup.2+, and X is at least one of Cl.sup., Br.sup., and I.sup.. Use of the light valve in the manufacture of a light control device and a method of controlling light transmittance by using the light valve are also provided.

Systems for separating Ra from a mixture comprising at least Ra, Pb, Bi, and Th are provided. The systems can include: a first vessel housing a first media and Th or Bi; a second vessel in fluid communication with the first vessel, the second vessel housing a second media and Pb; and a third vessel in fluid communication with the second vessel, the third vessel housing a third media and Ra, wherein at least one of the first, second, or third medias are different from the other media.

Methods for separating Ra from Pb, Bi, and Th are provided, the methods can include: providing a first mixture comprising Ra, Pb, Bi, and/or Th; providing a system that can include: a first vessel housing a first media; a second vessel in fluid communication with the first vessel, the second vessel housing a second media; and a third vessel in fluid communication with the second vessel, the third vessel housing a third media; and exposing the first mixture to the first media within the first vessel then, through the fluid communication, exposing the first remainder to the second media in the second vessel, then, through fluid communication, exposing the next remainder to the third media in the third vessel, the exposing separating the Th and Bi from the Ra and Pb, and the Ra from the Pb.

Methods for separating Ra from being associated with a media are also provided. The methods can include: exposing the Ra and media to a chelating agent to form a mixture comprising the Ra complexed with the chelating agent.

Disclosed herein is a polymeric film, the film comprising a polymeric matrix material, a plurality of perovskite nanocrystals and/or aggregates of perovskite nanocrystals dispersed throughout the polymeric matrix material. There is also disclosed a perovskite polymer resin composition, a perovskite-polymer resin composition, a perovskite ink and a method of forming a luminescent film using any one of the compositions or ink. Preferably, the perovskite material is a lead halide perovskite containing a cation selected from Cs, an alkylammonium ion, or a formamidinium ion. The polymeric matrix is preferably formed from monomers comprising a vinyl or an acrylate group.

A light valve containing ABX.sub.3 perovskite particles (200) suspended in a liquid suspension (300) that can control light transmittance is provided. The preferable ABX.sub.3 perovskite particles (200) are halide ABX.sub.3 perovskite particles wherein A is at least one of Cs.sup.+, CH.sub.3NH.sub.3.sup.+, and Rb.sup.+, B is at least one of Pb.sup.2+, Ge.sup.2+, and Sn.sup.2+, and X is at least one of Cl.sup., Br.sup., and I.sup.. Use of the light valve in the manufacture of a light control device and a method of controlling light transmittance by using the light valve are also provided.

Described are luminescent components with excellent performance and stability. The luminescent components comprise a first element including first luminescent crystals from the class of perovskite crystals, embedded a first polymer P1 and a second element comprising a second solid polymer composition, said second polymer composition optionally comprising second luminescent crystals embedded in a second polymer P2. Polymers P1 and P2 differ and are further specified in the claims. Also described are methods for manufacturing such components and devices comprising such components.

A main object of the present disclosure is to provide a novel cathode active material that may be used for a fluoride ion battery. The present disclosure achieves the object by providing a cathode active material used for a fluoride ion battery, comprising a composition represented by Pb.sub.2xCu.sub.1+xF.sub.6, wherein 0x<2.

Present invention provides a process for the synthesis of size and composition tunable colloidal PbMgS core and PbMgS/MS core shell quantum dots emitting in the near infrared (NIR) region of the spectrum in a single operation in a continuous flow reactor. M includes at least one of Cd, Mg, Zn and Cu metals.

A perovskite luminescent nanocrystal has a chemical formula represented by: Cs.sub.4BX.sub.6, wherein B includes one or more selected from the group consisting of Ge, Pb, Sn, Sb, Bi, Cu, and Mn, and X includes one or more selected from the group consisting of Cl, Br, and I, wherein the Cs.sub.4BX.sub.6 perovskite luminescent nanocrystal has a pure phase, and a molar ratio of Cs to B (Cs/B) in the Cs.sub.4BX.sub.6 perovskite luminescent nanocrystal is greater than 1 and less than 4.

Methods for producing ferric maltol compositions, such as ferric trimaltol, from elemental iron, and ferric maltol compositions produced by these methods and their uses are described.

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.