3D printing of highly conductive nanocomposites for the functional optimization of liquid sensors

The fabrication of highly conductive carbon nanotube/polylactic acid (CNTs/PLA) nanocomposites used as 3D printable conductive inks for fabrication of conductive scaffold structures applicable as liquid sensors was reported. Structures in form of scaffolds with different structural parameters, thickness of scaffolds, were fabricated using solvent-cast 3D printing method. The filament diameters were varied from 128 to 432 μm by changing the extrusion nozzle used for 3D printing within the range of 100?330 μm. IFS, number of printed layers, and the printed patterns were controlled by modifying a computer-aided design (CAD) software. The influence of four different structural parameters on the sensitivity of the printed scaffold liquid sensors was investigated. The thickness of the scaffolds varied from 0.17 to 1.11 mm by changing the number of printed layers from 2 to 10. The lowest liquid sensitivity was related to the scaffold with the lowest IFS which can be considered as the most compact structure. The number of filaments along the length and width of the scaffolds increases by decreasing the IFS leading to more intersections of the top and bottom neighboring filament layers. Printing highly conductive material in 3D can also be valuable for fabrication of complex conductive structures, useful for electronics in 3D circuits.