Three-dimensional flower-like FeCoNi/reduced graphene oxide nanosheets with enhanced impedance matching for high-performance electromagnetic wave absorption

Nanostructured magnetic metal/reduced graphene oxide (rGO) composites, benefiting from well-performed losses including high dielectric/magnetic losses, have garnered considerable interest as advanced microwave absorbers (MAs) in recent years. Optional approaches of unique trimetallic/rGO nanostructures, however, are still limited to attain high electromagnetic (EM) absorption and broad bandwidth as well as improved impedance matching. Herein, porous flower-like FeCoNi/rGO nanosheets, synthesized via magnetic-field-assisted (MFA) reduction, presents facilitated microwave absorption performance. The zigzag-like attachments of neighbored nanosheets constitute the porous flower-like architecture; average thickness of the nanosheets is 5-20 nm. The reduction process, determined by appropriate GO dosage, plays a key role to tune geometry and distribution of the flower-like nanosheet structures. The optimal sample, owning a relatively high surface area (157.3 m(2) g(-1)), achieves an impressive reflection loss (RL) intensity of - 75.95 dB and its maximum effective absorption bandwidth (RL <= -10 dB) is up to 4.69 GHz, along with improved impedance matching. This work provides a facile and alternative route for exploring other novel nanoalloy-based MAs. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The porous flower-like FeCoNi/rGO nanosheets synthesized via magnetic-field-assisted reduction exhibit excellent microwave absorption performance, with high reflection loss intensity and wide effective absorption bandwidth, along with improved impedance matching. The geometric shape and distribution of the flower-like nanosheets can be optimized through the reduction process using appropriate graphene oxide dosage. This study provides a facile and alternative route for exploring novel nanoalloy-based microwave absorbers.