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Microwave absorption is the process by which a material converts incident electromagnetic energy in the microwave frequency range into other forms of energy, principally heat, thereby reducing the energy that is reflected or transmitted from the material. When a microwave enters an absorbing material, its electromagnetic energy is dissipated through dielectric and magnetic loss mechanisms associated with the material’s complex permittivity and permeability, including conduction loss, dielectric polarization and relaxation, and magnetic resonance losses ^[1][2]. Effective microwave absorption requires both impedance matching, which facilitates the entry of electromagnetic waves into the material by minimizing surface reflection, and sufficient attenuation, which dissipates the electromagnetic energy that has entered the material. The absorption behavior is therefore governed by the frequency-dependent electromagnetic properties, impedance matching, and thickness of the absorbing layer ^[1][3]. In a real material, incident electromagnetic energy can be distributed among reflection, transmission, and absorption. Microwave absorbers are designed to favor the entry of electromagnetic waves into the material and their subsequent dissipation rather than strong surface reflection. For a metal-backed absorber, transmission is suppressed by the conductive backing, so the absorption performance is primarily determined by the reduction of reflection at the front surface ^[1]. Microwave absorption is related to, but distinct from, electromagnetic interference (EMI) shielding: shielding effectiveness can involve reflection, absorption, and multiple internal reflections, whereas microwave absorbers are specifically designed to minimize reflection and promote energy dissipation within the absorbing medium ^[2][3]. Microwave absorption performance is commonly evaluated by the fraction of incident electromagnetic power absorbed over a specified frequency band and is strongly dependent on dielectric and magnetic losses and impedance matching ^[1][2][3].