Remarkable Conductivity Design of FeCo2S4/MXene 2D Membrane Electrodes for Advanced Pseudocapacitance Characteristic Behavior

Supercapacitors (SCs) are promising energy supply systems for various electronics. In this work, we detailed the in situ growth of FeCo2S4 on MXene for asymmetric SCs. Notably, the digital model was first built to explore the relationship between wt (FeCo2S4) and capacitance performance, realizing the maximum theoretical capacity (3635.7 F g–1) prediction. Furthermore, it was discovered that the synergistic effect of the FeCo2S4/MXene heterojunction could dramatically improve conductivity and structural stability, which accelerated charge transmission at the electrode/electrolyte interface, resulting in a significant enhancement in electrochemical performance. The FeCo2S4/MXene electrode exhibited a higher capacitance of 2415.3 F g–1 and a prominent long-term stability of about 90.5%. And the FeCo2S4/MXene//AC declared an impressive energy density of 68.7 Wh kg–1 at a power density of 800 W kg–1. The FeCo2S4/MXene composite systems have great potential for advanced SC systems due to their facile assembly and remarkable electrochemical performance.