# GO@CNT@Fe₃O₄@CuO quaternary nanohybrids enhance dielectric-magnetic synergy for high-performance epoxy-based electromagnetic absorbers

## TL;DR

A new nanohybrid material improves electromagnetic absorption in epoxy composites, achieving high performance with low material loading.

## Contribution

A quaternary nanohybrid is introduced to enhance dielectric-magnetic synergy in electromagnetic absorbers.

## Key findings

- The nanocomposite achieved a minimum reflection loss of −37.5 dB at 10.25 GHz.
- It provided an effective absorption bandwidth of 3.2 GHz at 5.0 mm thickness.
- The material showed balanced permittivity and permeability for optimal impedance matching.

## Abstract

This study introduces a novel quaternary GO@CNT@Fe₃O₄@CuO core-shell nanohybrid designed to overcome impedance mismatch limitations in electromagnetic (EM) absorbers. Through stepwise synthesis, we integrated dielectric (GO, CNT), magnetic (Fe₃O₄), and semiconducting (CuO) components to create synergistic loss mechanisms. When incorporated at only 5 wt% into epoxy resin, the nanocomposite achieved exceptional X-band absorption with a minimum reflection loss of − 37.5 dB at 10.25 GHz and an effective absorption bandwidth of 3.2 GHz (9.0–12.2 GHz) at 5.0 mm thickness. The enhanced performance stems from balanced complex permittivity (ε′ = 6.1, ε″ = 2.6) and permeability (µ′ = 1.28, µ″ = 0.19), enabling optimal impedance matching and multi-mechanism attenuation through conduction loss, interfacial polarization, and magnetic resonance. This work establishes a design principle for low-loading, high-efficiency EM absorbers suitable for 5G and aerospace applications.