Improvement of microwave absorption properties of polyester coatings using NiFe2O4, X-doped g-C3N4 (X = S, P, and O), and MTiO3 (M = Fe, Mg, and Zn) nanofillers

Abstract

In recent decades, to reduce electromagnetic pollution, scientists focus on finding new microwave absorbers with effective performance, thin thickness, and broad bandwidth. In this work, the nanoparticles of NiFe2O4, X-doped g-C3N4 (M = S, P, and O), and MTiO3 (M = Fe, Mg, and Zn) were successfully synthesized using co-precipitation, specific heat program, and semi-wet sol–gel methods, respectively. The synthesized nanoparticles were utilized as absorption agents and polyester resin as the matrix. Morphology, particle size, crystal structure, and chemical composition of the prepared nanocomposites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffractometer (XRD), and energy dispersive X-Ray analysis (EDX), respectively. The microwave absorption performance of the coatings was also investigated by a vector network analyzer (VNA). Moreover, the effect of different parameters on the performance of absorbent coatings was studied by the Taguchi method and optimized to achieve an optimal absorbent. The results showed that the optimal nanocomposite has the reflectance loss (RL) less than − 30 dB (equal to absorption > 99%) at a high-frequency range (8–12 GHz) and 1 mm thickness. Furthermore, the addition of such novel nanoparticles to absorbents resulted in high values of attenuation constant (more than 200 dB/m) at the X-band. Therefore, the polyester coating filled with ZnTiO3, O-doped g-C3N4, and NiFe2O4 nanofillers can be considered a high-efficiency and low-density absorber.

A study on microwave absorption properties of polyaniline/nitrile rubber/graphene/Fe3O4 composites with a thickness of 0.7 mm and high flexibility

“…Z N , Z in , Z 0 exhibit the ability of the electromagnetic wave to enter the absorber, input impedance, and impedance of free space, respectively. The maximum value for Z N is 1 which exhibits the ideal impedance matching 18 . Z N is expressed as follows 19 : …”

“…The maximum value for Z N is 1 which exhibits the ideal impedance matching. 18 Z N is expressed as follows 19 :…”

Sustainability-driven photocatalysis: oxygen-doped g-C3N4 for organic contaminant degradation

“…After that, the precipitate is thermally processed to create oxygen-doped g-C 3 N 4 . 16 Solgi et al 16 fabricated O@g-C 3 N 4 using the same process and used oxalic acid as the oxygen source.…”

Tuning the Phase Structure of ZnTiO3 Support to Promote the Catalytic Activity of Pd/ZnTiO3 Catalyst for the CO Oxidative Coupling to Dimethyl Oxalate

“…As one of the titanium‐based perovskite oxides, ZnTiO 3 has attracted widespread attention in different frontier research fields due to its extraordinary potentials in electrode materials, [8] magnetic materials, [9] antibacterial materials, [10] gas sensors, [11] photocatalysis, [12,13] and heterogeneous catalysis [14,15] . It has been reported that cubic and hexagonal phases of ZnTiO 3 as catalyst support exhibit different catalytic performances in the steam reforming of methanol due to their different properties [14] .…”