Microstructural Regulation of Co TCPP by Acetylene Black: Enhanced Electrochemical Performance for Wearable Supercapacitors

Abstract

Abstract With the rapid development of wearable devices, flexible supercapacitors have become an important energy storage prototype due to their inherent flexibility and high power density. Two-dimensional metal-organic framework (2D MOF) nanosheets are widely used in energy storage systems due to their structural tunability and anisotropy. However, their high surface energy tends to lead to aggregation, which results in poor dispersion and rheology of formulated inks and inhomogeneity of printed electrodes. Existing methods involve surface modulation by capped organic ligands, yet ignore the inherent conductivity and stability of MOFs. To overcome the low conductivity and aggregation problems of 2D MOFs, we adopted a novel approach combining mechanical intercalation and surface functionalization of cobalt-based porphyrin frameworks (Co TCPP) with acetylene black (AB). The unique microstructure of the composite material leads to favorable changes in the electronic properties of AB, which reduces the overall internal resistance and promotes rapid charge transfer. For this purpose, we have prepared micro-supercapacitors (MSCs) using dispensing printing technology. This integrated material has excellent mechanical flexibility and maintains 92% specific capacitance even under extreme bending and torsion. This study highlights the potential of integrating 2D MOFs with carbon-based materials (e.g., acetylene black) for a variety of applications in wearable electronics, and provides a guiding scheme for future micro-modulation of 2D MOFs using conductive materials.