Effect of hydrogenation on the microwave absorption properties of BaTiO3 nanoparticles

Microwave absorbing materials (MAMs) have numerous important applications in electronic communications, signal protection, radar dodging, etc. Although it has been proposed as a promising MAM, BaTiO3 has a high reflection coefficient at the interface with air, causing a large reflection. Thus, its efficiency of microwave absorption is not satisfactory. Here, we report that hydrogenation has largely improved the microwave absorption of BaTiO3 nanoparticles. Hydrogenation is performed on BaTiO3 nanoparticles by treating pristine BaTiO3 nanoparticles at 700 degrees C for 4 hours in a pure H-2 environment. The enhanced microwave absorption efficiency with a reflection loss value (-36.9 dB) is attributed to the increased resonance of polar rotations with the incident electromagnetic field which is amplified by the increased interfacial polarization caused by the built-in electrical field along the boundaries between different grains created within these nanoparticles.