72 results about "Cation exchange reaction" patented technology

The invention provides an achievement method of cation exchange of a lead halide perovskite quantum dot material. The method includes the steps of: 1) adding Cs2CO3, octadecene and oleic acid into a reaction bottle A, and feeding argon with stirring; 2) adding PbCl2 and octadecene into a reaction bottle B and feeding argon with stirring; 3) adding MnCl2 and octadecene into a reaction bottle C and feeding argon with stirring; 4) heating the reaction bottles A, B and C, adding oleic acid and oleylamine into the reaction bottles B and C, and continuously heating the reaction bottles B and C; 5) adding the solution in the reaction bottle A to the solution in the reaction bottle B, so that after a reaction is carried out in the reaction bottle B for a preset time, a CsPbCl3 perovskite quantum dot material solution is produced; 6) adding the solution in the reaction bottle C to the solution in the reaction bottle B to carry out a cation exchange reaction in the reaction bottle B to generate Cs(Pb<1-x>Mn<x>)Cl3. The method, on the basis of not damaging the appearance of the lead halide perovskite quantum dot material, can control the ratio of lead in the lead halide perovskite quantum dot material, so that a problem of lead poisoning of the lead halide perovskite quantum dot material can be solved.

The invention relates to a method for preparing a CdS-Bi2S3 composite nanocrystalline by utilizing a partial cation exchange reaction, which is characterized by comprising: firstly, a flower-like SdS nanocrystalline is synthesized by a hydrothermal method; and then, the flower-like SdS nanocrystalline and a newly formed Bi2S3 nanocrystalline are combined by means of the partial cation exchange reaction so as to integrate the properties of Cds and Bi2S3 into the single composite nanocrystalline. The method has the advantages that in the process of synthesizing the composite nanocrystalline, nucleation and growth of the second phase material Bi2S3 can be avoided, thereby achieving effective composite of the CdS and the Bi2S3 in a nano-scale; and experimental operation is simple, the cost is cheap, and the requirement on experimental equipment is low. The method can be extended to the synthesis of other binary system nano composite materials.

The invention relates to montmorillonite modified silicone fluid sealant and a process for preparation, the fluid sealant is composed of silicone crude rubber, metasilicate montmorillonite, organic treating agent, cross-linker, plasticizing agent, viscosity increaser and initiating agent, the process for preparation comprises cation exchange reaction between the montmorillonite and the organic treating agent, then, organic modified montmorillonite is evenly scattered in the silicone crude rubber, and then the cross-linker, the initiating agent and other additives are added, solidified, and shaped. The fluid sealant has good binding power, excellent weather fastness, perfect ultra-violet resisting anti-aging performance and water-resistant performance to bridges, tunnels and road projects and concrete elements of buildings, can keep excellent flexibility and stretch rate in environments of sun, rain, snow, extreme high or extreme low-temperature, has non pollution to environment and road surface, and can be widely applied to seal concrete dilatation joints in the bridges, the tunnels, the road projects, airport runway, construction works and the like, to repair cracking concrete structures, and to treat metal surface with anti-corrosion.

This invention discloses a method for synthesizing organic-inorganic bentonite composite. The method comprises: utilizing bentonite as the main material, performing inorganic modification through cation-exchange reaction by using hydroxyl aluminum aqueous solution, torrefying to obtain hydroxyl-containing aluminum-pillared bentonite with high porosity and high specific surface area, and reacting between the hydroxyls and silylation agent to graft silane groups onto aluminum-pillared bentonite and obtain organic-inorganic bentonite composite. The organic-inorganic bentonite composite has both the advantages of inorganic pillared bentonite such as high porosity and high specific surface area, and those of organic bentonite such as high organic carbon content and high hydrophobicity thus can be used to treat organic waste gases and wastewater with a good effect by surface adsorption as well as distribution.

The present invention provides a quantum dot (QD) composite material, a preparation method, and a semiconductor device. The method includes synthesizing a first compound at a predetermined position, synthesizing a second compound on the surface of the first compound, the second compound and the first compound having a same alloy composition or having different alloy compositions, and forming the QD composite material through a cation exchange reaction between the first compound and the second compound. The light-emission peak wavelength of the QD composite material experiences one or more of a blue-shift, a red-shift, and no-shift. The method uses the QD successive ionic layer adsorption and reaction (SILAR) synthesis method to precisely control layer-by-layer QD growth and the QD one-step synthesis method to form a composition-gradient transition shell. The QD composite materials prepared by the disclosed method not only achieve higher light-emitting efficiency, but also meet the comprehensive requirements of semiconductor devices and corresponding display technologies on QD composite materials.

The invention relates to a multimode anti-counterfeiting method based on luminescent doped quantum dots, belonging to the technical field of anti-counterfeiting. The method comprises the following steps of selecting luminescent doped quantum dots which can emit fluorescence by excitation, preparing printable luminescent ink and printing it as anti-counterfeit label, and emitting fluorescence by the anti-counterfeit label under excitation; immersing the anti-counterfeit label in solution A, and the fluorescence disappearing after the cation exchange reaction; immersing the anti-counterfeit label after fluorescence disappearance in solution B, and recovering the fluorescence after cation exchange reaction. When cation exchange reaction is adopt, the reaction temperature is low, the reactiontime is short, the operation is simple, and the change of the fluorescence signal is easy to identify. The identification process provides further anti-counterfeit verification means, which improves the confidentiality of anti-counterfeit and the difficulty of imitation. After the fluorescence signal disappears, the recovery of the fluorescence signal can be realized, and the anti-counterfeit identification can be further carried out. The recognition process requires the use of specific cationic solution to react, which further increases the security of anti-counterfeiting.