Synthesis and Electromagnetic Absorbing Properties of Titanium Carbonitride with Quantificational Carbon Doping

Abstract

Recent studies to explore the enhanced electromagnetic properties of TiN and TiC reported that TiNC has a good performance in EM wave absorption. We prepared TiNC with quantificational percentages of carbon doping in this work. Nanotitanium oxide precursor was prepared via sol–gel method, then submicron TiN(1–x)C x with different carbon content (x = 0, 0.2, 0.4, 0.6, 0.8) was obtained via solid–gas reaction by nitriding at 900 °C with nitrogen and carbon doping at 1700 °C with argon. The composition and structure of TiN(1–x)C x change with the increase of carbon content, the lattice distortion and dipole moments were introduced into TiN crystal via carbon doping which leads to optimization of the electromagnetic properties. The influence of carbon doping was analyzed, and at carbon = 0.8, the attenuation factor “α” and impedance matching “Δ” of the sample achieved a better balance that results in a better wave absorbing effect. The resulting bandwidth lower than −10 dB is in the range 11.1 to 13.6 GHz, and the reflection loss reached to −40.1 dB at 12.4 GHz with the sample thickness of 1.32 mm. The frequency of maximum reflection loss obeys the quarter-wavelength matching model. TiN(1–x)C x shows good electromagnetic absorbing properties and it is in accordance with the “thin, light, wide, strong” application requirements of microwave absorption materials.

Flaky FeSiAl alloy-carbon nanotube composite with tunable electromagnetic properties for microwave absorption

“…It is known that good impedance matching which requires the balance between permittivity and permeability is the prerequisite for EM wave entering absorber. The impedance matching degree ∆ of the FeSiAl-8 and FeSiAl/MWCNTs can be calculated in the following equations 45 46 :…”

Epoxy‐Based Ceramic‐Polymer Composite with Excellent Millimeter‐Wave Broadband Absorption Properties by Facile Approach

“…The second term describes the conduction current and resultant conduction loss under the incidence of EM wave. This kind of current would transform the incident EM energy into other forms of energies and such process would take place at all frequencies . It has been known that three kinds of polarization mechanisms could contribute to the dielectric loss of the filler phase in the measured frequency range: 1) electronic polarization that generally produces dielectric loss at ultrahigh frequencies; 2) ionic polarization because of the introduction of Nb 5+ ions, which possess a higher valence state and easier to move inside the lattice under external electric field; and 3) conduction polarization due to the existence of oxygen vacancies, which originates from the mismatch between the ionic radius of Nb 5+ and Fe 3+ in the lattice .…”

Applications of Microwave Materials: A Review

“…65 Hong et al investigated microwave absorption properties of titanium carbonitride and found that thin microwave absorbers can be realized by optimal doping of carbon in the compound. 66 Silica-nickel-carbon composites are also reported to have good absorption characteristics. 67 A metasurface containing graphene patches as shown in Fig.…”

“…Table IV gives a clear picture of different microwave-absorbing materials that have been discussed in this paper and their absorption characteristics. 64 8.2-18 2.5 Titanium carbonitride (TiN 0:2 C 0:8 ) 66 11.1-13.6 1.32 40 wt.% Silica-Ni-C composite Shelly hollow microspheres 67 5.7-18 2.4-4 2 wt.% CNT/rice husk ash composite 127 12.48-16.47 2 40 wt.% Rice husk/nontoxic glue binder 139 6.3-7.1 37.5 ( # pyrolysis temperature, *À20 dB absorption frequency bandwidth).…”