Tannin-Based Resins for 3D printing of Porous Carbon Architectures

Carbon structures, unlike metals or polymers, can hardly be directly implemented in additive manufacturing, and their sustainable nature is extremely limited. In this work, we demonstrate that porous carbon structures can be obtained by laser stereolithography of acrylate–tannin mixed resins, followed by a pyrolysis step. By adjustment of the initial acrylate/tannin ratio in the resin, the density and volume shrinkage of the resultant carbon, and consequently the mechanical properties of the corresponding carbon-based architectures, could be modified. The moderate electrical conductivity of the structures, reaching about 7 S cm–1, and their broad-band absorption in microwaves open up possibilities for electrochemical or electromagnetic applications. Thus, the possibility of obtaining complex freestanding structures with imperceptible warpage, low volume shrinkage, and adjustable density offers an opportunity to develop 3D-printed carbon materials with a significant proportion of bio-based precursors, which can be easily adapted for a large number of applications.