Related Experiment Video
Updated: Jun 17, 2025

Niobium Oxide Films Deposited by Reactive Sputtering: Effect of Oxygen Flow Rate
Published on: September 28, 2019
Application of N-doped NiCo2O4/NiO/Co3O4composites rich in oxygen vacancies in electromagnetic wave absorption
Junkang Li1, Yiqing Yang2, Yongqing Ma1
1School of Materials Science and Engineering, Anhui University, Hefei 230601, People's Republic of China.
Abstract:
In this work, N-doped and oxygen vacancy-rich NiCo2O4/NiO/Co3O4composites are synthesized by the direct calcination method. Noticeably, by changing the additive concentrations of urea dissolved in DMF (N-N dimethylformamide), the electromagnetic wave (EMW) absorption abilities of NiCo2O4/NiO/Co3O4composite effectively. A maximum reflection loss (RLmax) value at 12.94 GHz for a 2.8 mm thick sheet is -29.76 dB, while its effective absorption bandwidth (RL < -10 dB) reaches 4.21 GHz. In-depth research of possible mechanisms of EMW absorption enhancement. Owing to its simple preparation method and superb EMW absorption properties, the NiCo2O4/NiO/Co3O4composites have a chance to be suitable candidates for high-property EMW absorbers.
Related Concept Videos
Molecular Spectroscopy: Absorption and Emission
Electromagnetic Waves in Matter
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the...
IR Absorption Frequency: Hybridization
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...

