Microwave-induced energy activation: Mechanisms and material advances

Microwave ignition is an emerging non-contact energy activation technique offering rapid response, selective heating, and high controllability compared with conventional ignition. Owing to volumetric energy deposition and localized field enhancement, it has attracted growing interest in energetic materials activation and propulsion systems. This review systematically summarizes the mechanisms of microwave-material interactions, highlighting impedance matching, dielectric and magnetic losses, and energy localization that govern ignition behavior. The main ignition pathways, including direct dielectric heating, absorber-assisted ignition, and plasma-assisted ignition, are compared in terms of power threshold and ignition delay. Representative microwave-responsive materials, such as MICs, MXenes, MOFs, and their derivatives, are discussed with emphasis on structure-property-ignition relationships. Engineering aspects, including microwave sources, resonant cavities, antenna coupling, and thermal management, are further reviewed. Finally, challenges and prospects toward quantitative modeling, frequency-targeted design, and integrated ignition systems are outlined, providing a unified framework linking mechanisms, materials, and practical ignition applications.