Microwave Absorption Performance of SiC/ZrC/SiZrOC Hybrid Nanofibers with Enhanced High-Temperature Oxidation Resistance

Abstract

In carbide ceramics, ZrC has a high melting point, high hardness, and excellent thermal conductivity and electrical conductivity. It can be used as a suitable additive phase for SiC nanomaterials to enhance its high-temperature resistance to oxidation and its microwave absorption property. In our work, heterogeneous SiC/ZrC/SiZrOC hybrid nanofibers with different ZrC contents are prepared using polycarbosilane and zirconium acetylacetonate as raw materials through electrospinning and hightemperature pyrolysis processes. With an increase in the ZrC content from 0 to 10 wt %, the electrical conductivity of the hybrid nanofibers increases from 0.3448 to 2.5676 S/cm, and the average diameter decreases from 800 to 200 nm. The SiC/ZrC/SiZrOC hybrid nanofibers result in improved microwave-absorbing capability with a minimum reflection loss of about −40.38 dB at 14.1 GHz, a thickness of 4 mm, and antioxidant properties at 600 °C. These results prove that the heterogeneous SiC/ZrC/SiZrOC hybrid nanofibers have reasonable electrical conductivity. This results in dielectric loss, which is mainly because of the added ZrC. The dipole polarization, interfacial polarization, quarter-wave cancellation, and conductivity loss are the main reasons for the enhanced microwave absorption.

Recent Advances in Applications of Ceramic Nanofibers

“…The unique properties of CNFs such as high surface area, extraordinary length, low density, high porosity, and thermo-mechanical properties [40,41] qualify them for many different applications. This chapter covers a review of their applications related to tissue engineering [35,36,[42][43][44][45][46][47], sensors [32-34, 48, 49], water remediation [50][51][52][53][54][55][56], batteries [57][58][59][60][61][62][63], catalyst supports/catalysts [64][65][66][67][68][69][70][71], electromagnetic interference (EMI) shielding [72][73][74][75][76][77][78][79], and thermal insulation materials [26,[79][80][81][82], etc. A list of the recent studies about ceramic nanofibers by electrospinning method is presented in Table…”

“…The superior EMI shielding properties (high reflection loss together with wider EAB) imparted the composite nanofibers the potential to be used as reinforcements in polymer and ceramic matrix composites with EMI shielding properties [76]. Huo et al [72] prepared heterogeneous SiC/ZrC/SiZrOC hybrid nanofibers with different ZrC contents and analyzed them in terms of electrical conductivity, average diameter, and microwave-absorbing capability. When the ZrC concentration increased from 0 to 10 wt.%, decrease in average nanofiber diameter from 800 nm to 200 nm and increase in electrical conductivity from 0.3448 to 2.5676 S cm −1 were observed.…”

“…When the ZrC concentration increased from 0 to 10 wt.%, decrease in average nanofiber diameter from 800 nm to 200 nm and increase in electrical conductivity from 0.3448 to 2.5676 S cm −1 were observed. The minimum reflection loss was measured as −40.38 dB at 14.1 GHz for the SiC/ZrC/SiZrOC hybrid nanofibers and they were suggested as promising high temperature microwave-absorbing materials [72]. Using a combined process of electrospinning and calcination, Huo et al [73] produced silicon carbide/carbon (SiC/C) hybrid nanofibers, which possessed a high aspect ratio and a scaly surface.…”

Effect of incorporation of hafnium diboride nanofibers on thermomechanical properties of carbon fiber–phenolic composites

“…Among these composites, carbon fiber/phenolic (C/Ph) composites are widely utilized for the purpose of ablative thermal protection attributed to their high specific strength and ablative nature. The ablation characteristics of the C/Ph composites are strongly dependent on the type of matrix and the additives incorporated into them 2 . Effective char formation during pyrolysis process and low flammability coupled with low thermal conductivity make the phenolic resin a popular candidate as a matrix material for ablative composites.…”

Microwave-Assisted Air Epoxidation of Mixed Biolefins over a Spherical Bimetal ZnCo-MOF Catalyst

“…Since microwaves were used for heating first in the last century, they has been widely used in various fields due to their high speed and effective heating effect. , Nowadays, the use of microwave treatment of chemical reactions has become a hot spot. , Microwaves heat a sample by converting electromagnetic energy into heat, , and the heating rate is uniform and fast. Since the process of microwave heating is energy conversion rather than heat transfer, − heating can be started and stopped quickly as well as noncontact heating, so materials can be selectively heated. According to the experimental results, it was found that compared with conventional heat sources (such as steam and electric heaters), the use of microwave heating could achieve a higher product yield and better chemical reaction selectivity. − In addition, using microwave heating could shorten the reaction time and increase the reaction rate.…”