Sodium-based dual-ion batteries have received increased attention owing to their appealing cell voltage (i.e., >3 V) and cost-effective features. However, the development of high-performance anode materials is one of the key elements for exploiting this electrochemical energy storage system at practical levels. Here, we report a source-template synthetic strategy for fabricating a variety of nanowire-in-nanotube MS_xTe_y@C (M = Mo, W, Re) structures with an in situ-grown carbon film coating, termed as nanocables. Among the various materials prepared, the MoS_1.5Te_0.5@C nanocables are investigated as negative electrode active material in combination with expanded graphite at the positive electrode and NaPF₆-based non-aqueous electrolyte solutions for dual-ion storage in coin cell configuration. As a result, the dual-ion lab-scale cells demonstrate a prolonged cycling lifespan with 97% capacity retention over 1500 cycles and a reversible capacity of about 101 mAh g⁻¹ at specific capacities (based on the mass of the anode) of 1.0 A g⁻¹ and 5.0 A g⁻¹, respectively.

Mixed transition metal sulfides with hollow structures hold great promise for energy-related applications. However, most of them are in the powder form, which should be mixed with unwanted polymer binders and conductive agents. In this study, a facile two-step strategy has been developed to grow mesoporous and hollow Ni–Zn–Co–S nanosword arrays (NSAs) on a nickel foam (NF) substrate with robust adhesion, which involves the hydrothermal growth of bimetallic Zn–Co-ZIF NSAs on NF and subsequent transformation into hollow Ni–Zn–Co–S NSAs through the sulfurization process. Benefiting from the unique structural and compositional advantages as well as directly grown conductive substrate, the Ni–Zn–Co–S-0.33 NSAs/NF electrode exhibits the best electrochemical performance when investigated as a binder-free electrode for supercapacitors. Impressively, the Ni–Zn–Co–S-0.33 NSAs/NF electrode delivers a high areal capacity of 1.11 mA h cm⁻² at the current density of 10 mA cm⁻², and the corresponding specific capacity is as high as 358.1 mA h g⁻¹. Moreover, an asymmetric supercapacitor (ASC) device based on the Ni–Zn–Co–S-0.33 NSAs/NF as the positive electrode and Bi₂O₃/NF as the negative electrode has been successfully fabricated, and can deliver a high energy density of 91.7 W h kg⁻¹ at a power density of 458 W kg⁻¹ and maintain the energy density of 66.9 W h kg⁻¹ at a high power density of 6696 W kg⁻¹. The electrochemical results suggest that the hollow Ni–Zn–Co–S NSAs would possess great potential for applications in high-performance supercapacitors.

Sodium-ion hybrid capacitors (SIHCs) have shown great promise in achieving both high energy density and high power density by virtue of synergizing the merits of batteries and capacitors. However, the lack of favorable anode material with superior sodium-ion storage capability is still a major challenge in the development of high-performance SIHCs. Herein, we report the design and synthesis of a promising sodium-ion storage nanohybrid with FeS quantum dots embedded in three-dimensional (3D) inverse opal (IO)-structured N-doped carbon (3D-IO FeS-QDs@NC). By virtue of the robust 3D conductive architecture, the 3D-IO FeS-QDs@NC nanohybrid exhibits favorable features of excellent electron/ion transport kinetics, superior structural stability, as well as impressive sodium-ion storage capability with high specific capacity, outstanding rate capability, and ultra-long cyclic stability. Such highly desirable sodium storage performance inspired us to study their potential application in SHICs by coupling with commercial activated carbon (AC) as a cathode. The as-developed SHICs can deliver a maximum energy density and power output of 151.8 W h kg⁻¹ and 9280 W kg⁻¹, respectively, and an excellent cycling lifespan with 91% capacity retention after 5000 cycles at 1 A g⁻¹, which holds promise for bridging the performance gap between conventional batteries and capacitors.