Nuclear energy provides base-load electric power, yet reactor maintenance, nuclear fuel reprocessing, and radiopharmaceutical manufacturing generate environmental safety requirements concerning ionizing radiation (gamma rays, X-rays, neutron flux) and airborne radionuclides (such as volatile radioiodine species $^{129}text{I}$/$^{131}text{I}$, radioactive aerosols, and noble gases). Traditional lead (Pb) aprons and shields are heavy, cause mechanical fatigue, and carry heavy-metal toxicity. Meanwhile, standard activated carbon air filters risk thermal ignition and structural degradation under elevated temperatures or high radiation fields.

Aerogel composites featuring high thermal stability, inorganic frameworks, and specific surface areas serve as lightweight radiological protection and active airborne radionuclide capture media for nuclear facilities. By incorporating high-atomic-number (high-$Z$) metal oxide nanoparticles (such as bismuth Bi, barium Ba, tungsten W, or lead Pb) or neutron-absorbing elements (such as boron B or lithium Li) into silica, graphene, or alumina aerogel networks during sol-gel synthesis, materials developers fabricate lightweight nanocomposites that attenuate ionizing radiation.

These heavy-metal/aerogel composites provide radiation attenuation through distinct physical mechanisms. The uniformly dispersed high-$Z$ nanoparticles attenuate gamma and X-ray photons via photoelectric absorption and Compton scattering events. Concurrently, aerogel backbones rich in light elements (such as hydrogen or boron) attenuate fast neutrons via elastic scattering collisions, capturing slow thermal neutrons. Compared to dense metallic lead sheets, heavy-metal/aerogel composites reduce overall mass by over 60% while maintaining equivalent radiation attenuation parameters. This mass reduction improves mobility when deployed in protective suits and transportable radiation shields.

For radioiodine capture and aerosol filtration, aerogel filtration media functionalized with organic moieties (such as primary amines, thiols, or metal-organic frameworks, MOFs) exhibit high uptake capacities. The open nanoporous network imposes low pressure drops while physically intercepting airborne sub-micron radioactive aerosols. Simultaneously, surface amine or metallic sites undergo chemisorption and charge-transfer complexation with volatile radioiodine species (such as elemental $text{I}_2$ or organic $text{CH}_3text{I}$), trapping them within the micropore architecture. Even under high temperatures (exceeding 200°C) and strong ionizing radiation fields, these functionalized aerogel filtration matrices maintain structural integrity and radionuclide retention, providing an inorganic barrier for nuclear safety systems.