Recent advances in radio-frequency negative dielectric metamaterials by designing heterogeneous composites

Negative Permittivity Behaviors Derived from Dielectric Resonance and Plasma Oscillation in Percolative Bismuth Ferrite/Silver Composites

“…Moreover, some other composites with dielectric and metal particles (Ni, Fe, Cu, etc.) as fillers showed similar phenomena. − Li et al attributed the negative permittivity behavior of BiFeO 3 /Bi 2 Fe 4 O 9 composites at about 1 GHz to dielectric resonance. Generally, the negative permittivity behavior obtained by plasma oscillation has a wide range and good tunability, but the loss is extremely high and the order of magnitude is large, limiting its use in dielectric capacitors and high-power microwave filters. , Dielectric resonance produces a small loss of negative permittivity, but the resonance often occurs at a fixed frequency, resulting in poor tunability. , Achieving a combination of two negative permittivity behaviors in the same material can address these challenges.…”

“…12,22 Dielectric resonance produces a small loss of negative permittivity, but the resonance often occurs at a fixed frequency, resulting in poor tunability. 21,23 Achieving a combination of two negative permittivity behaviors in the same material can address these challenges.…”

Hydroxyapatite coatings: a critical review on electrodeposition parametric variations influencing crystal facet orientation towards enhanced electrochemical sensing

“…To mitigate these mechanical and electrical restrictions, HAp is generally coupled as a composite with metallic and metal oxide substrates of Ti, Mg, and carbon-based composites to act as a backbone of sorts in enhancing its mechanical properties 9 and in providing a point of electrical contact and conduction. Nanocomposite coatings are considered an effective strategy in the fabrication of heterogeneous materials 10,11 resulting in improvement in physico-chemical properties, [12][13][14][15][16][17][18] mitigating detrimental degradation, [19][20][21] and in enhancing its applicative aspects towards increased efficacy, [22][23][24][25] in reinforcement, [26][27][28][29] and sustainability. 30 The fabrication of these nanocomposites offers a certain degree of flexibility in their respective field of application.…”

Outstanding electromagnetic interference shielding performance in hydrothermally derived vanadium pentoxide–polyaniline aerogels

“…are widely accepted as promising light shields. 9,10 Since EMI shielding effectiveness is proportional to the electrical conductivity, higher EMI SE demands a higher weight percentage of the conducting filler, which eventually increases the shield's density. Also, high conductivity causes strong secondary reflection, which harms the environment and living systems.…”