2results about How to "Improving Impedance Matching Performance" patented technology

This invention belongs to the field of electromagnetic wave absorbing materials technology, specifically relating to a nickel-boron-doped cobalt-based layered carbon absorbing material and its preparation method. This invention utilizes a cobalt-based boron imidazole precursor framework as a template, and forms a two-dimensional layered layered double hydroxide (LDH) through a chemical oxidation etching process using nickel ions. This LDH is then subjected to high-temperature reduction to obtain the nickel-boron-doped cobalt-based layered carbon material. This material leverages the unique properties of two-dimensional materials to achieve high impedance matching, allowing electromagnetic waves to enter the absorber at a significant rate. Furthermore, the material's excellent dielectric polarization and magnetic coupling attenuate the electromagnetic waves entering the absorber. The material achieves a minimum reflection loss of -60.1 dB and a maximum effective absorption bandwidth of 6.24 GHz, giving it excellent electromagnetic wave absorption capabilities. The preparation method of this invention is simple and easy to mass-produce.

This invention discloses a graphene aerogel surface microwave absorbing material supported on Fe / N co-doped hollow carbon nanospheres and its preparation method. First, a reduced graphene oxide aerogel is prepared using graphene oxide as a raw material. Then, hollow Fe3O4 magnetic nanoparticles are prepared via a hydrothermal method using FeCl3·6H2O and ammonium acetate as raw materials. Finally, Fe3O4 / PPy / reduced graphene oxide aerogel is prepared by in-situ polymerization, and the graphene aerogel supported on Fe / N co-doped hollow carbon nanospheres is obtained through high-temperature heat treatment. The graphene aerogel surface microwave absorbing material supported on Fe / N co-doped hollow carbon nanospheres of this invention exhibits excellent dielectric and magnetic losses. Simultaneously, the magnetic Fe nanoparticles in the material can effectively convert electromagnetic wave energy, achieving excellent microwave absorption performance, and showing great potential in next-generation cutting-edge advanced nanocomposite materials.