Hybrid Manufacturing of 3D Hierarchical Porous Carbons for Electrochemical Storage

Abstract

Carbon is one of the most attractive electrode materials for electrochemical energy storage. An ideal electrode structure requires a pore distribution ranging from nanoscale to milliscale to simultaneously enable efficient mass transfer, enlarge the specific surface area, and minimize the electrical resistance. Here, a novel hybrid method to fabricate carbon electrodes with a designable hierarchical pore structure is presented. The proposed manufacturing combines stereolithography, pyrolysis, and chemical activation, which contribute to producing pores in millimeter, micrometer, and nanometer, respectively. The prepared hierarchical microarchitectural material outperforms the commercial carbon paper by five times in current density. Further enhancement in the electrochemical performance can be achieved through optimizing the distribution of hierarchical pores, which is proved feasible in the applications of vanadium redox flow battery and supercapacitor applications.