Simple, controllable fabrication and electromagnetic wave absorption properties of hollow Ni nanosphere

Wen, Guosheng; Liu, Ying; Sun, Gehui; Wang, Yingchun

doi:10.1007/s10854-018-0488-9

Cited by 6 publications

(1 citation statement)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, specific reflection loss (S RL ) is an indicator which is more appropriate to evaluate microwave absorbing performance. The S RL value of NHCS@NiO/Ni could reach 220.2 dB mg −1 mm −1 much larger than those of other previously reported absorbers including hollow carbon sphere, [ 45 ] NiS 2 hollow spheres, [ 46 ] hollow Ni nanosphere, [ 47 ] NiFe 2 O 4 hollow nanosphere, [ 45 ] carbon hollow spheres, [ 48 ] hollow carbon sphere, [ 49 ] NiCo 2 O 4 hollow sphere, [ 50 ] S‐doped hollow sphere, [ 51 ] NiO/NiFe 2 O 4 /Ni foam, [ 52 ] and Ni/NiO/Cu@C [ 53 ] (Figure 5l and Table S2, Supporting Information). In addition, the attenuation constant (α) mainly represented the microwave dissipation capability by dielectric loss, which higher α value was attributed to stronger dissipation ability.…”

Section: Resultsmentioning

confidence: 70%

NiO/Ni Heterojunction on N‐Doped Hollow Carbon Sphere with Balanced Dielectric Loss for Efficient Microwave Absorption

Zhang

et al. 2023

Small

View full text Add to dashboard Cite

Hollow carbon spheres are potential candidates for lightweight microwave absorbers. However, the skin effect of pure carbon‐based materials frequently induces a terrible impedance mismatching issue. Herein, small‐sized NiO/Ni particles with heterojunctions on the N‐doped hollow carbon spheres (NHCS@NiO/Ni) are constructed using SiO2 as a sacrificing template. The fabricated NHCS@NiO/Ni displayed excellent microwave absorbability with a minimum reflection loss of −44.04 dB with the matching thickness of 2 mm and a wider efficient absorption bandwidth of 4.38 GHz with the thickness of 1.7 mm, superior to most previously reported hollow absorbers. Experimental results demonstrated that the excellent microwave absorption property of the NHCS@NiO/Ni are attributed to balanced dielectric loss and optimized impedance matching characteristic due to the presence of NiO/Ni heterojunctions. Theoretical calculations suggested that the redistribution of charge at the interfaces and formation of dipoles induced by N dopants and defects are responsible for the enhanced conduction and polarization losses of NHCS@NiO/Ni. The simulations for the surface current and power loss densities reveal that the NHCS@NiO/Ni has‑ applicable attenuation ability toward microwave under the practical application scenario. This work paves an efficient way for the reasonable design of small‐sized particles with well‐defined heterojunctions on hollow nanostructures for high‐efficiency microwave absorption.

show abstract