3D Printing of Monolithic Carbon Electrodes with Hierarchical Pores Enabled by Nucleated Resin

Optical-based additive manufacturing offers a promising approach for the precise fabrication of monolithic carbon electrodes with complex geometries. However, the conventional fabrication process, which involves three sequential steps—3D printing, pyrolysis, and chemical activation—is both time-intensive and technically challenging. In this study, a photosensitive resin incorporating K 2 CO 3 as a pore-forming templates is developed and subsequently photocured into the desired structures via a digital light processing 3D printer. By employing this resin, the chemical activation step is effectively integrated into the pyrolysis process, thereby reducing the overall fabrication procedure from three steps to two. The resulting monolithic carbon structures exhibit hierarchical porosity across four distinct length scales, spanning from the nanometer to the sub-millimeter range. The electrochemical surface area of the 3D-printed monolithic carbon electrode is 7.2 times greater than that of the commercial carbon paper. When applied in a vanadium redox flow cell, the monolithic electrodes demonstrate an energy efficiency improvement of 20.7% compared to solid-wall electrodes and 2.6 times that of the carbon paper electrode.