Controllable synthesis and morphology-dependent microwave absorption properties of iron nanocrystals

Microwave absorption properties of FeCo-coated carbon fibers with varying morphologies

“…It was believed that large surface-to-volume ratio corresponds to strong absorption since an increase in interfacial polarization will be achieved as a result of increased number of surface atoms with unsaturated bonds [49]. This is consistent with previous results reported by other researches who found that fillers with a high aspect ratio (such as nanoflakes) exhibited better microwave absorption properties as compared to those with low aspect ratio (such as nanoparticles) [50][51][52]. The findings presented in this paper clearly demonstrate that the morphology of Fe-Co coatings can effectively affect the EM wave absorption properties of the FeCo-coated carbon fibers although further experimental and theoretical work is needed to clarify the mechanisms behind.…”

Flowerlike iron oxide nanostructures and their application in microwave absorption

“…Surface anisotropy and exchange energy caused by the exchange effect between grains have been proven to be important for nanocrystalline particles [25]. Generally speaking, the multiresonance phenomena were contributed from the natural resonance and exchange resonance [26,27]. In Fig.…”

Enabling highly efficient and broadband electromagnetic wave absorption by tuning impedance match in high-entropy transition metal diborides (HE TMB2)

“…Notably, the boosting magnetic loss capability in HE TMB 2 -3 especially in the high frequency range as shown in Fig. 10( [17]), metal and alloys (Fe [18], FeCo [19], CoNi [20]), carbides (HfC/SiC [25], HfC [47], TaC [47]), and high-entropy borides (HE REB 6 [49], HE REB 6 /HE REBO 3 [49], HE REB 6 /HE REB 4 [50]). It is worth mentioning that the EM wave absorbers locating in lower-right corner in Fig.…”

“…For instance, dielectric loss-type absorbers include carbon fiber (CF) [6], carbon nanotube (CNT) [7], reduced graphene oxide (rGO) [8], conductive polymer [9], oxides (silicon oxide [10], zinc oxide [11], etc. ), transition metal sulfides [12], silicon carbide [13], and 2D transition metal carbides/ nitrides/carbonitrides (MXenes) [14], and magnetic loss-type absorbers consist of ferrites [15][16][17] and magnetic metals [18][19][20]. Although dielectric loss-type EM absorbing materials exhibit high attenuation constant (α) mainly derived from dielectric loss, they are still hindered by limited absorption capacity and narrow effective absorption bandwidth (EAB) due to the mismatch between the complex permittivity and the complex permeability.…”

“…12(e) and 12(f). Besides, the effective absorptions GHz), X band (8-12 GHz), and Ku band(12)(13)(14)(15)(16)(17)(18). To illustrate the superior EM wave absorption performance of HE TMB 2 s, Fig.13summarizes the optimized EAB and RL values of three HE TMB 2 s and some currently reported EM wave absorbers of sulfides based (CF@MoS 2[6], MoS 2[12]), MXenes (Ti 3 C 2[14]), ferrites (Fe 3 O 4[15], C@BaMg 0.2 Co 0.8 TiFe 10 O 19 [16], Ba 0.8 La 0.2 Co 0.9 Zn 1.1 Fe 16 O 27…”