The capability of three-dimensional printed cut-wire metasurfaces to harvest energy in frequencies around 2.4 GHz, is studied in this paper. Cut-wire metasurfaces were constructed using the Fused Filament Fabrication technique. In particular, two metasurfaces, consisting of different materials were produced. The first was constructed using Polylactic Acid as starting material. Then, the printed metasurface was covered with a thin layer of conductive silver paint, in order to achieve good electrical conductivity. The other metasurface was built using commercially available, conductive Electrifi. Both metasurfaces exhibit good energy harvesting behavior, in the frequency band near 2.4 GHz. Their harvesting efficiency is found to be almost three times lower than that obtained for conventional PCB-printed cut-wire metasurfaces. Nevertheless, all of the experimental results presented here strongly corroborate that three-dimensional-printed metasurfaces can be potentially used to harvest energy in the 2.4 GHz frequency band.

Rectangular, millimeter-scale complementary split ring resonators were fabricated, employing the so-called Computer Numerical Control method, combined with a home-built mechanical engraver. Their electromagnetic performance was thoroughly investigated with respect to their dimensions in the frequency regime between 2 and 9 GHz via combining experiments and corresponding theoretical simulations, wherein a considerably effective consistency was obtained. Moreover, their sensing response was extensively investigated against various aqueous solutions enriched with typical fertilizers used in agriculture, as well as detergents commonly used in every-day life. Corresponding experimental results evidently establish the capability of the studied metasurfaces as potential sensors against water pollution.