High-Density Dual Atoms Pairs Coupling for Efficient Electromagnetic Wave Absorbers.

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Dual atoms (DAs) offer tunable structures and high atomic efficiency for coordination engineering.
• Designing high-density, heterogeneous DA pairs for improved electromagnetic wave (EMW) absorption remains a significant challenge.

Purpose of the Study:

• To construct high-density Ni-Cu dual atom (DA) absorbers on a nitrogen-rich carbon substrate.
• To investigate the synergistic effects of coupled Ni-Cu DA pairs on EMW absorption performance.
• To explore the mechanism behind enhanced EMW absorption through charge redistribution and polarization loss.

Main Methods:

• Precise construction of high-density Ni-Cu dual atom (DA) absorbers.
• Characterization of metal loading and EMW absorption properties (effective absorption bandwidth, reflection loss).
• Theoretical calculations to elucidate the electronic structure and charge transfer mechanisms.

Main Results:

• Achieved a high metal loading of 4.74 wt.% for Ni-Cu DA absorbers.
• Extended the effective absorption bandwidth (EAB) from 0 to 7.8 GHz.
• Obtained a minimum reflection loss (RLmin) of -70.96 dB at 3.60 mm, achieving >99.99% energy absorption.
• Demonstrated electron-rich site transfer from N to Cu, inducing asymmetric polarization loss.

Conclusions:

• The synergistic effect of coupled Ni-Cu DA pairs significantly enhances EMW absorption.
• This work presents a viable strategy for preparing high-density DA pairs for advanced materials.
• Precisely tuned coordination symmetry at the atomic level is crucial for optimizing EMW absorption.