Tailoring Cross-Scale Structures in Dual-Transition Metal MXene Aerogels for Robust Microwave Absorption

Area of Science:

• Materials Science
• Electromagnetics
• Nanotechnology

Background:

• Achieving broadband microwave absorption with thin profiles is difficult due to impedance and attenuation conflicts.
• Developing advanced electromagnetic functional materials requires innovative structural designs.

Purpose of the Study:

• To fabricate dual-transition metal TiNbCx/rGO/Fe3O4 aerogels with cross-scale structural tailoring.
• To enhance microwave absorption performance by optimizing material structure from nanoscale to millimeter scale.

Main Methods:

• Fabrication of aerogels using freeze-drying technique.
• Incorporation of Nb atoms for enhanced polarization loss at the nanoscale.
• Regulation of aerogel wall porosity using dimensional disparity between rGO and MXene at the microscopic level.
• Construction of stepped gradient architecture optimized by a genetic algorithm at the macroscopic level.

Main Results:

• The TiNbCx/rGO/Fe3O4 aerogel (TNRF-1) achieved an effective absorption bandwidth (EAB) of 6.24 GHz at 2.0 mm thickness with a minimum reflection loss of -51.47 dB.
• The optimized stepped gradient structure achieved an EAB of 14.45 GHz with superior angular robustness.
• The cross-scale structural tailoring effectively reconciled impedance and attenuation.

Conclusions:

• The developed cross-scale paradigm offers a feasible approach for advanced electromagnetic functional materials.
• The dual-transition metal aerogels demonstrate significant potential for high-performance microwave absorption applications.