The unique lithium‐ion battery anodes consisting of interconnected nano‐architectures with high specific surface areas, adequate buffer space to tolerate the volume change, excellent conductivities, and admirable mechanical stabilities demand for next‐generation lithium‐ion battery (LIB). Herein this report, highly interconnected and self‐assembled tungsten disulfide nanosheets (WS2 NS) array is constructed through simple hydrothermal process. The ultrathin nature of nanosheet array can not only efficiently buffer the huge volumetric change but also abbreviate the Li‐ion and electron diffusion path. As expected, the ultrathin WS2 nanosheets array is endowed with excellent structural stability and also very fast electrochemical kinetics, and hence extraordinary lithium‐storage performance, such as delivering high capacities of 813.33 mAh g−1 at a C rate of C/8, admirable rate capability and good cycling stability, that is, 242 and 226 mAh g−1 at a C rate of 1 and 2 C, respectively, up to 600 cycles.

As an attractive family of anode material for lithium-ion battery (LIB), transition metal dichalcogenides (TMDs) with high energy density has been emerging very fast. Among various TMDs, tungsten disulphide (WS 2) with its intrinsically layered structure is a promising alternative anode candidate because of its high theoretical capacity. However, WS 2 usually suffers from poor cycling stability due to its large volume change during lithiation and delithiation process. Herein, we have synthesized carbon free nanostructured plate like WS 2 (NP-WS 2) by an easy one pot hydrothermal synthesis process. Without introducing any conducting carbonaceous materials, the P-WS 2 showing extraordinary lithium storage properties. At a Crate of C/8, the observed initial lithiation and delithiation capacities are 682.0 and 555.7 mAh g À 1 , respectively. During the cycling stability test at a rate of C/4, even after 200 cycles P-WS 2 delivered high delithiation capacity of 380 mAh g À 1. Even without incorporation of conducting carbonaceous materials, NP-WS 2 demonstrated extraordinary lithium storage performance which indicates its potential as an alternative high capacity anode material for lithium-ion battery.

The multiple oxidation states of redox‐active materials enable them to store high‐energy better than the commonly used carbon‐based electrode materials. Accounting for these advantages, designing asymmetric supercapacitors by coupling redox‐active materials as positive electrodes with carbon‐based negative electrodes becomes a very attractive strategy. Herein, reduced graphene oxide‐wrapped hexagonal WO3 nanorod (rGO‐WO3 NR) by simple hydrothermal synthesis method is synthesized. Because of improved reaction kinetics resulting from the close contact between rGO and WO3 NRs, rGO‐WO3 NR demonstrates superior electrochemical properties than pure WO3. Motivated by the very high areal capacitance (2.5 F cm−3 at the applied current of 30 mA cm−2), an asymmetric SC device by combining rGO‐WO3 NR with activated carbon is assembled. The as‐assembled rGO‐WO3 NR//activated carbon asymmetric supercapacitor device demonstrates outstanding electrochemical performance in an operating voltage window of 1.2 V, admirable cycling stability of ≈95% (even after 14 000 cycles), with an energy density of 24.1 Wh Kg−1 at a power density of 1532.6 W Kg−1. These demonstrate the combination of redox‐active materials with high energy density can importantly boost the energy storage capacity of a supercapacitor.

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