5results about How to "Small average pore size" patented technology

The invention relates to a rare earth element Ho modified Ni-based catalyst and a preparation method and application thereof, the rare earth element Ho modified Ni-based catalyst comprises an active component and an auxiliary agent, the active component is NiO, and the auxiliary agent is Ho2O3; the molar ratio of Ho to Ni in the Ni-based catalyst modified by the rare earth element Ho is (0.002-0.008): 1. The auxiliary Ho2O3 is introduced, and the molar ratio of Ho to Ni in the rare earth element Ho modified Ni-based catalyst is regulated to be (0.002-0.008): 1, so that on one hand, the specific surface area and pore volume of NiO can be increased, the average pore size can be reduced, and exposure of active sites is promoted; on the other hand, edge dislocation and defect structures are formed through induction, generation of oxygen vacancies is facilitated, and therefore the catalytic performance is further improved.

This invention relates to the field of sodium-ion battery technology, specifically to a modified hard carbon material and its preparation method, a negative electrode sheet, and a sodium-ion battery. The modified hard carbon material is obtained by mixing and grinding a hard carbon precursor with naphthalene at a mass ratio of 5-9:1-5, followed by a two-stage heat treatment. This invention utilizes the gas-phase infiltration and high-temperature carbonization of naphthalene at specific temperatures. In the first stage, naphthalene is converted into gaseous molecules. Its small kinetic diameter allows it to penetrate deep into the micropores of the hard carbon precursor and be adsorbed under capillary action and pressure difference. In the second stage, naphthalene undergoes pyrolysis, transforming in situ into an amorphous soft carbon layer. This achieves uniform and deep filling of carbon within the micropores of the hard carbon, effectively reducing the average pore size. This not only promotes the pre-desolvation of solvated sodium ions but also helps to obtain an ultrathin and stable NaF-rich solid electrolyte interface film, improving the rate performance of the material. Furthermore, this process is simple, efficient, and low-cost, which is beneficial for large-scale production.

This invention discloses a method for preparing a composite nanofiltration membrane by electrospinning with a mixed solvent. The method includes dissolving polyacrylonitrile (PAN) in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), stirring the solution until it is completely transparent under water bath heating, and allowing it to stand to remove bubbles to obtain a PAN electrospinning solution; electrospinning the PAN solution to form a membrane, and then hot-pressing and drying it to obtain a PAN nanofiber membrane; impregnating the PAN nanofiber membrane with a piperazine (PIP) aqueous solution, tumbling it with a rubber roller, and adding a trimesoyl chloride (TMC) n-hexane solution to synthesize polyamide (PA) as the top layer to obtain a PA / PAN composite nanofiltration membrane. This composite membrane has high flux and rejection rate for both salts and dyes.

This invention discloses a method for preparing silicon-carbon composite anode materials using porous graphite. First, a porous carbon material with a large number of uniformly distributed nano- to micron-sized pores is prepared using a physical foaming method, and then graphitized at high temperature to obtain porous graphite. Next, the porous graphite is pulverized to obtain graphite powder with a cratered surface structure, and then mixed with a certain proportion of nano-silicon and ball-milled to embed the nano-silicon into the cratered structure on the graphite powder surface. Finally, the mixed material is carbon-coated to obtain a silicon-carbon composite anode material for lithium-ion batteries. Applications of this composite material are also provided. In this invention, nano-silicon and graphite have good electrical contact, greatly improving the electrochemical performance of the silicon-carbon composite anode material. Simultaneously, graphite can buffer the volume expansion of the silicon material. The cratered structure on the graphite surface improves the lithium intercalation reaction of the silicon-carbon composite anode material, improving the rate capability and low-temperature performance of lithium-ion batteries.

The invention provides a porous polymer foam material prepared based on a high internal phase emulsion template method and application thereof, the preparation method comprises the following steps: (1) mixing a vinyl monomer, a cross-linking agent, alkyl (meth) acrylate, an emulsifier, magnetic nanoparticles and a tracer agent to obtain an oil phase component; mixing water, electrolyte and an initiator to obtain a water-phase component; adding the water-phase component into the oil-phase component, and emulsifying to obtain a water-in-oil high-internal-phase emulsion; (2) depositing the water-in-oil type high internal phase emulsion obtained in the step (1) on a carrier substrate, and applying a pulsed magnetic field; (3) carrying out plasma treatment on the water-in-oil type high internal phase emulsion obtained in the step (2); curing in an eddy current induction area; in the step (3), a Fourier transform infrared spectrometer is adopted to monitor the concentration of each component on line, and signals are transmitted to a model prediction controller. The preparation method solves the problems of surface adhesion, oxygen inhibition and incomplete curing in the curing process.