Three-Dimensional Architecture Reduced Graphene Oxide–LiFePO₄ Composite: Preparation and Excellent Microwave Absorption Performance

Abstract

The present work reports preparation of 3D composites of reduced graphene oxide (RGO) with coral-like LiFePO₄ particles in two steps, which involves the fabrication of LiFePO₄ particles by the solvothermal method and the subsequent preparation of RGO/coral-like LiFePO₄ composites by the etching method. The microwave absorption properties of LiFePO₄ particles, coral-like LiFePO₄ particles, and the RGO/coral-like LiFePO₄ composites were studied. Our results show that the as-prepared RGO/coral-like LiFePO₄ composites exhibit significantly improved microwave absorption properties compared with the pure LiFePO₄ particles and coral-like LiFePO₄ particles. The RGO/coral-like LiFePO₄ composite (S-60) possesses optimized reflection loss (RL) performance with an RL value of -61.4 dB and a broad effective absorption bandwidth of 4 GHz (from 11.36 to 14.88 GHz and 16.32 to 16.8 GHz) at the matching thickness of only 2.4 mm. This demonstrates that the RGO/coral-like LiFePO₄ composites can be superior candidates for lightweight and high-efficiency microwave absorbers.