The Synergy of Retiform Mos2 Nanosheets with 3d Porous Structure Electrode Membrane for Ultrastable Sodium-Ion Hybrid Capacitor

Sodium-ion hybrid capacitors (SICs) were considered as promising candidates for large-scale energy storage systems due to their exceptional combination of high energy density and high power density. However, the challenge lied in addressing the imbalance of reaction kinetics and the mismatch in charge storage capacity between slow Faraday battery-type anodes and fast non-Faraday capacitive cathodes. In this paper, facing the requirement for rapid Na+ intercalation on anode, retiform MoS2 nanosheets were synthesized via a facile hydrothermal method and in-situ composited with an interpenetrating network porous electrode membrane to fabricate an integrated electrode (CM@MoS2). Among them, the MoS2 nanosheets were chemically bonded to the electrode membrane and uniformly distributed within the membrane pore structure, effectively preventing volume expansion and detachment during prolonged cycling. The meticulously designed structural arrangement and synergistic effect of MoS2 and the electrode membrane created favorable conditions for Na+ storage. As anodes in sodium ions battery, 472.2 mA h g−1 of reversible capacity was obtained at 0.05 A g−1. And the retention rate of reversible capacity was as high as 94.2% even after undergoing 1000 cycles at a high current density of 0.2 A g−1. After assembled CM@MoS2//AC SICs, an impressive reversible capacity retention rate of 83.4% was harvested even after undergoing 5,000 cycles at a current density of 2 A g−1 with an average capacity decay per cycle as low as 0.00332%. Owing to excellent nano-structural design and sodium storage behavior, CM@MoS2//AC SICs exhibited an exhilarating energy density of 117 W h kg−1 at a power density of 100 W kg−1, demonstrating excellent dual-function features. Even at a high power density of 10 kW kg−1, they still achieved 50.8 W h kg−1. The application of architectonics on Faraday battery-type anodes can be anticipated to offer insights and concepts for the future rational design of sodium storage materials with enhanced electrochemical properties on SICs.