Coaxial Core–Shell Carbon–Tin Sulfide Nanohybrids as High‐Performance Electrodes for Long‐Life Supercapacitors

As emerging high‐power energy devices, supercapacitors require electrode materials that enable fast charge transport at high current and long‐term stability. In this regard, integrating electric double‐layer capacitance with pseudocapacitive behavior in metal sulfide–carbon nanohybrids is a promising strategy to enhance both capacitance and cycling stability. Herein, a coaxial core–shell carbon–tin sulfide nanohybrid is designed as a high‐performance binder‐free electrode using a rapid plasma‐assisted dry approach, enabling uniform overgrowth of layered SnS on vertical nanocarbon (VCN) to form SnS@VCN. The strong interface interaction and conductive carbon framework synergistically enhance ion transport and structural stability, resulting in one of the best SnS‐based electrode performances by delivering a high specific capacitance of 577 F g ⁻¹ (242 C g ⁻¹ ) at 3 A g ⁻¹ and retaining 72% of its capacitance at 12 A g ⁻¹ with a remarkable cyclic stability of 115% capacitance retention after 10 000 cycles. An asymmetric SnS@VCN//AC device further delivers a specific capacitance of 17.8 F g ⁻¹ and ultrahigh cyclic stability, with 140% capacitance retention after 5000 cycles. The interplay between the plasma‐tailored interface and hierarchical core–shell morphology effectively overcomes the rate and stability limitations of conventional battery‐type electrodes, offering a scalable, environmentally benign pathway toward ultra‐stable, high‐rate energy storage materials for advanced supercapacitors.