Inducing Directional Charge Delocalization in 3D‐Printable Micro‐Supercapacitors Based on Strongly Coupled Black Phosphorus and ReS2 Nanocomposites

The growing interest in so‐called interface coupling strategies arises from their potential to enhance the performance of active electrode materials. Nevertheless, designing a robust coupled interface in nanocomposites for stable electrochemical processes remains a challenge. In this study, an epitaxial growth strategy is proposed by synthesizing sulfide rhenium (ReS2) on exfoliated black phosphorus (E‐BP) nanosheets, creating an abundance of robust interfacial linkages. Through spectroscopic analysis using X‐ray photoelectron spectroscopy and X‐ray absorption spectroscopy, the authors investigate the interfacial environment. The well‐developed coupled interface and structural stability contribute to the impressive performance of the 3D‐printed E‐BP@ReS2‐based micro‐supercapacitor, achieving a specific capacitance of 47.3 mF cm−2 at 0.1 mA cm−2 and demonstrating excellent long‐term cyclability (89.2% over 2000 cycles). Furthermore, density functional theory calculations unveil the positive impact of the strongly coupled interface in the E‐BP@ReS2 nanocomposite on the adsorption of H+ ions, showcasing a significantly reduced adsorption energy of −2.17 eV. The strong coupling effect facilitates directional charge delocalization at the interface, enhancing the electrochemical performance of electrodes and resulting in the successful construction of advanced micro‐supercapacitors. The exfoliated black phosphorus@sulfide rhenium (E‐BP@ReS2) nanocomposite with a strong‐coupled interface is prepared that can trigger the electronic redistribution and produce abundant active sites for efficient adsorption of electrolyte ions, thereby enabling the realization of high‐performance 3D‐printed flexible micro‐supercapacitors.