Two-dimension Graphite Nanosheets Loaded Magnetic Metal Nanocapsules With Electromagnetic Wave Absorption And Anti-bacterial Performance

In this paper,we fabricated two-dimensional(2D)graphite nanosheet decorated by nanocapsules with transition metal nickel or cobalt as the core and carbon as the shell(2D graphite/Ni@C,Co@C nanocomposite)by the arc discharge method.From this method,the amount of 2D graphite nanosheets,the defect density,the shell thickness of nanocapsule and the content of magnetic metal core can be controlled by the addition amount of acetonitrile and the composite of the anode target material.These changes can make the influence of the morphology,structure and electromagnetic wave(EMW)absorbent properties of the material.At the same time,excellent anti-bacterial performance for Escherichia coli(E.coli)was developed to meet the more needs of multifunctional applications in special environment.The main achievements of this paper are as follows:1.By varying the shell and changing the magnetic composition of the core for 2D graphite/Ni@C nanocomposite to tune the EMW matching and obtain excellent wave absorption performance.We developed 2D graphite/Ni@C nanocomposite structure by arc-discharge plasma technique for one step.By changing the addition amount of acetonitrile while adjusting the thickness of the C shell and the doping N,we study the changes of the structure and performance for the absorber.It was found that when 10 ml of acetonitrile was added,with a mass filling ratio of 30 wt.%and an absorber thickness of 2 mm,the minimum reflection loss(RL)value reached-36.08 dB,while the effective absorption bandwidth(EAB)reached 5.12 GHz.To further compare the effect of magnetic medium content in the target material,it was found that when the nickel content was 3.4 wt.%,the 2D graphite/Ni@C nanocomposite had the best absorbent performance.The results indicate that the absorbent performance is mainly characterized by the dielectric loss.The doping-N in the acetonitrile and the presence of heterointerfaces which leads to the dipole polarizations make the mechanism.The magnetic loss of the material is mainly from the natural resonance.2.By varing the doping-N of 2D graphite/Co@C nanocomposite to adjust the EMW matching and obtain excellent wave absorption performance..The microstructure and wave absorption performance of 2D graphite/Co@C nanocomposite related to different addition amount of acetonitrile.It was found that the nanocomposite structure prepared by adding 20 ml of acetonitrile has the optimal absorption performance,with an EAB of 4.88 GHz when the mass fraction is 40 wt.%.The magnetic loss property is also enhanced by replacing cobalt to nickel.The new cobalt-based absorber 2D graphite/Co@C nanocomposite provides a reference direction for the development of multi frequency band strong absorption absorbing materials.3.We developed 2D graphite/Ni@C nanocomposite with the addition of 10 ml acetonitrile which had great anti-bacterial performance for Escherichia coli(E.coli).We study the E.coli anti-bacterial performance of 2D graphite/Ni@C nanocomposite with the addition of 10 ml acetonitrile.It was found that the antibacterial rate exceeded 90%for 24 hours,which proved that the composite had great antibacterial performance.The physical cutting function from the nanostructure and oxidative stress caused by the release of nickel ions make the 2D graphite/Ni@C nanocomposite become an excellent E.coli anti-bacterial sources.As an efficient bifunctional nanocomposite with EMW absorption and anti-bacterial performance,2D graphite/Ni@C nanocomposite has created new possibilities and greatly increased the potential value for the practical application of multifunctional absorbing materials.