Enhanced microwave absorption properties of N-doped ordered mesoporous carbon plated with metal Co

Shen, Guozhu; Xu, Yanqiao; Liu, Bin; Du, Peng; Li, Yang; Zhu, Jun; Zhang, Ding

doi:10.1016/j.jallcom.2016.04.181

Cited by 48 publications

(18 citation statements)

References 42 publications

(35 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The high specific surface area and pore volume benefit from the steam activation as mentioned in our previous study. 41 Electromagnetic Parameters Analysis. Figure 4 shows the frequency dependence of the electromagnetic parameters of samples NOMC and CoFe 2 O 4 /NOMC composites measured by VNA in the frequency range of 0.5−18 GHz.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

See 1 more Smart Citation

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

Shen

Mei

et al. 2017

J. Phys. Chem. C

Self Cite

View full text Add to dashboard Cite

Lightweight nitrogen-doped ordered mesoporous carbon (NOMC) with high specific surface area and pore volume have been prepared through self-assembly and subsequent heat treatment route. The spherical NOMC particles are decorated with CoFe2O4 nanoparticles via coprecipitation method to enhance their microwave absorption property. The electromagnetic parameters of the NOMC and CoFe2O4/NOMC composites are measured and the microwave reflection loss properties are evaluated in the frequency range of 0.5–18 GHz. The results show that both the real part and imaginary part of permittivity of NOMC totally decline and the real part of permeability increases with the introduction of ferrite. However, the negative values of the imaginary part of the complex permeability appear for the CoFe2O4/NOMC composites, which may be caused by enhanced eddy current effect due to the introduction of ferrite. The reflection loss results exhibit that the CoFe2O4/NOMC composites have excellent microwave absorption performances. The absorption bandwidth less than −10 dB reaches 5.0 GHz (11.9–16.9 GHz) for 40-F/NOMC composite (40 wt % ferrite) with 1.5 mm of thickness and the minimum reflection loss value is up to −38.3 dB at 3.9 GHz for 30-F/NOMC composite with 4.0 mm of thickness. The excellent absorption properties derive from the synergistic effect between dielectric loss of NOMC and magnetic loss of ferrite and better impendence matching at air and ferrite/NOMC composite interface. Thus, the lightweight ferrite/NOMC composites exhibit their great potential as microwave absorbing materials.

show abstract

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…In our previous research, magnetic cobalt coated nitrogen-doped ordered mesoporous carbons have been prepared by low-temperature hydrothermal and electroless plating method. 41 However, the electroless plating is high-cost due to the low efficiency of reduction reaction from metal ions to metals.…”

Section: ■ Introductionmentioning

confidence: 99%

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

Shen

Mei

et al. 2017

J. Phys. Chem. C

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is discovered that all samples except for S600 show the broad diffraction peak at 24.1°, which associates with the characteristic peak of (002) for graphitic carbons. The (002) peak of S600 moves left slightly due to the increased interlayer distance, which results from the higher temperature . For S400, the diffraction peaks at 35.5°, 43.1°, 57.0°, and 62.7° can be attributed to (122), (220), (232), and (040) crystal planes of Fe 3 O 4 (PDF#76-0956), respectively.…”

Section: Results and Discusionmentioning

confidence: 99%

“…The (002) peak of S600 moves left slightly due to the increased interlayer distance, which results from the higher temperature. 23 For S400, the diffraction peaks at 35.5°, 43.1°, 57.0°, and 62.7°can be attributed to (122), ( 220), (232), and (040) crystal planes of Fe 3 O 4 (PDF#76-0956), respectively. With respect to S500, the peaks of 35.4°, 56.9°, and 62.5°corresponding to the lattice planes of (311), (511), and (440), respectively, can be assigned to Fe 3 O 4 (PDF#19-0629).…”

Section: ■ Results and Discusionmentioning

confidence: 99%

The Outside-In Approach To Construct Fe₃O₄ Nanocrystals/Mesoporous Carbon Hollow Spheres Core–Shell Hybrids toward Microwave Absorption

Cheng

Cao

et al. 2017

ACS Sustainable Chem. Eng.

197

View full text Add to dashboard Cite

It is widely accepted that building a core−shell structure is an effective way to modify impedance matching behavior and induce interfacial polarization relaxtion. In this work, we adopted a novel impregnation process and subsequent calcination treatment to construct Fe 3 O 4 nanocrystals/mesoporous carbon hollow spheres (MCHS) core− shell hybrids. From the perspective of microwave absorption, MCHS possess favorable dielectric loss ability and lightweight features. Fe 3 O 4 could produce magnetic loss and regulate impedance matching characteristics. Besides, hollow voids and mesopores facilitate microwave absorption, while multiple interfacial polarization induced between Fe 3 O 4 nanocrystals and MCHS contributes to microwave attenuation. Combining these advantages, a maximum reflection loss value of −60.2 dB at 15.5 GHz and a broad effective bandwidth of 5.7 GHz can be achieved for the as-prepared sample at a thickness of 2.3 mm. Furthermore, the excellent microwave absorption properties with a ultrawide bandwidth of 8.0 GHz (10.0−18.0 GHz) at 2.6 mm of thickness was achieved. Therefore, the as-prepared hybrids can act as a lightweight and broadband microwave absorber; moreover, the corresponding method could be a sustainable and low-cost route for designing multicore−shell hybrids.

show abstract

“…Due to the limitations of the method, the 500 nm macropores is too large to be represented in the specific surface area data, so the macropores has no remarkable impact on the SSA of the macroporous Fe 3 C/N-doped carbon nanocomposites. The Fe 3 C/N-doped carbon hybrid nanocomposites have a larger SSA compared with the pure N-doped nanofibers, which indicates that the mass fraction of iron plays a major role in the specific surface area of these materials 45 , 46 . Besides, the iron mass fraction of this macropores nanofibers is smaller than the nanofibers with solid structure 47 , 48 , so the SSA of the macroporous nanocomposites is smaller than the solid nanocomposites.…”

Section: Resultsmentioning

confidence: 99%

Solid and macroporous Fe3C/N-C nanofibers with enhanced electromagnetic wave absorbability

Liu

Yuan

Sun

et al. 2018

Sci Rep

View full text Add to dashboard Cite

A series of solid and macroporous N-doped carbon nanofibers composed of Fe3C nanoparticles (named as solid Fe3C/N-C NFs, solid Fe3C/N-C NFs-1, solid Fe3C/N-C NFs-2, macroporous Fe3C/N-C NFs, macroporous Fe3C/N-C NFs-1 and macroporous Fe3C/N-C NFs-2, respectively) were prepared through carbonization of as-electrospun nanofiber precursors. The results show that the magnetic Fe3C nanoparticles (NPs) dispersed homogeneously on the N-doped carbon fibers; as-prepared six materials exhibit excellent microwave absorption with a lower filler content in comparison with other magnetic carbon hybrid nanocomposites in related literatures. Particularly, the solid Fe3C/N-C NFs have an optimal reflection loss value (RL) of −33.4 dB at 7.6 GHz. For solid Fe3C/N-C NFs-2, the effective absorption bandwidth (EAB) at RL value below −10 dB can be up to 6.2 GHz at 2 mm. The macroporous Fe3C/N-C NFs have a broadband absorption area of 4.8 GHz at 3 mm. The EAB can be obtained in the 3.6–18.0 GHz frequency for the thickness of absorber layer between 2 and 6 mm. These Fe3C–based nanocomposites can be promising as lightweight, effective and low-metal content microwave absorption materials in 1–18 GHz.

show abstract

Enhanced microwave absorption properties of N-doped ordered mesoporous carbon plated with metal Co

Cited by 48 publications

References 42 publications

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

The Outside-In Approach To Construct Fe₃O₄ Nanocrystals/Mesoporous Carbon Hollow Spheres Core–Shell Hybrids toward Microwave Absorption

Solid and macroporous Fe3C/N-C nanofibers with enhanced electromagnetic wave absorbability

Contact Info

Product

Resources

About

Enhanced microwave absorption properties of N-doped ordered mesoporous carbon plated with metal Co

Cited by 48 publications

References 42 publications

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

Microwave Electromagnetic and Absorption Properties of N-Doped Ordered Mesoporous Carbon Decorated with Ferrite Nanoparticles

The Outside-In Approach To Construct Fe3O4 Nanocrystals/Mesoporous Carbon Hollow Spheres Core–Shell Hybrids toward Microwave Absorption

Solid and macroporous Fe3C/N-C nanofibers with enhanced electromagnetic wave absorbability

Contact Info

Product

Resources

About

The Outside-In Approach To Construct Fe₃O₄ Nanocrystals/Mesoporous Carbon Hollow Spheres Core–Shell Hybrids toward Microwave Absorption