Electromagnetic properties of 3D-printed carbon-BaTiO3 composites

3D-printed carbon structures filled with BaTiO3 nanoparticles were investigated in low (20 Hz-1 MHz) and microwave (26-37 GHz) frequency ranges. These structures possess rather high electrical conductivity in the low-frequency range (about several S/cm) and excellent dielectric properties in the microwave range. The electrical transport is thermally activated and can be attributed to electron transport through various defects. The electromagnetic properties of the investigated structures in the microwave range are very attractive. For example, the absorption of a 2 mm-plate with 46 wt. % of BaTiO3 at 30 GHz is 50%. The impact of BaTiO3 nanoparticles on the dielectric properties of the hybrid structures is positive over a wide frequency range, and the highest dielectric losses are observed for structures with 46 wt. % BaTiO3.