4 results about "Main group element" patented technology

The application provides a main group element ion doped zero-dimensional metal halide fluorescent sensing material and a preparation method and application thereof, and belongs to the technical field of fluorescent sensing materials. The main group element ion doped zero-dimensional metal halide microcrystal is synthesized by a solvothermal method, the strong dependence of two thermal coupling energy levels of the main group element ion on temperature is utilized, the main group element ion doped zero-dimensional metal halide shows an obvious temperature dependence evolution trend of fluorescence lifetime and fluorescence intensity at low temperature, and dual-mode (fluorescence intensity ratio / fluorescence lifetime) high-sensitivity temperature detection in a liquid helium temperature region can be realized. The synthesis method is simple in process and easy to control in synthesis conditions, the obtained material shows extremely high relative sensitivity in the liquid helium temperature region, has high practical application value, can be used as a novel optical temperature sensing material, and can be used for temperature detection in various extreme temperature regions.

This invention discloses a sulfide solid electrolyte comprising a substrate and co-doped elements, including M and N, where M≠N and M and N are transition metals or main group elements with different valence states. M is used to replace cation sites in the substrate, and N is used to replace anion sites in the substrate. M and N have a co-doping combination relationship, replacing either cation or anion sites. Based on this, the invention also discloses a method for preparing the above material. The invention has the following technical advantages: the material bulk effectively prevents the initiation and penetration of Na dendrites. The heterovalent co-doping strategy is precisely designed to ensure that while enhancing mechanical stiffness, the ion transport mechanism is not impaired, maintaining a high level of superionic conductivity. This avoids the use of complex and expensive external composite materials or multilayer interface coatings to enhance mechanical properties in ASSSIBs, simplifying the manufacturing process and reducing manufacturing costs.

A manufacturing method of a lithium ion secondary battery is provided. A positive electrode active material having a layered rock salt type crystal structure, such as lithium cobaltate, is provided with two regions on the surface thereof, wherein the inner region is a non-stoichiometric compound containing a transition metal such as titanium, and the outer region is a compound of a main group element such as magnesium oxide. Each of the two regions has a rock salt type crystal structure. The layered rock salt type crystal structure of the inner region and the two regions of the surface layer portion are topologically derived, whereby changes in the crystal structure of the positive electrode active material due to charging and discharging can be effectively suppressed. Furthermore, because the outer coating layer in contact with the electrolyte uses a compound of a main group element that is chemically stable, a secondary battery with superior cycle characteristics can be provided.

The application relates to the technical field of solid electrolytes, in particular to a co-doped sodium-based sulfide solid electrolyte and a preparation method and application thereof, wherein a Na2S-NaD nanoeutectic precursor is prepared by pre-high-energy ball milling of a sodium source and sodium halide, then the precursor is mixed with the remaining raw materials and sintered at a low temperature of 300-450 DEG C, so that the product forms a nanocrystal-glass composite structure which cannot be obtained by a traditional high-temperature solid-phase method. The unique structure can eliminate the inherent grain boundary impedance of the crystalline material, provide isotropic and continuous three-dimensional transmission channels for sodium ions, significantly reduce the diffusion barrier, and realize ultra-high ionic conductivity far exceeding that of the same-component crystalline material. Meanwhile, the application realizes multi-element synergistic doping by adopting the main group elements M of IV / V to partially replace the position of phosphorus elements and co-substitute the cations with fixed tungsten element doping, so that the lattice can be stabilized, stress can be released, the sodium ion diffusion barrier can be reduced, and the synergistic improvement of high air stability, high structural stability and high ionic conductivity can be realized.