Facile and High‐Efficient Synthesis of High‐Performance Supercapacitor Electrode Materials Based on the Synergistic Intercalation and Oxidation of Layered Tungsten Disulfide

The electrochemical performance of tungsten oxide (WO 3 ) is closely related to its morphology and lattice symmetry. However, current synthetic approaches are typically limited by product controllability, environmental friendliness, and low scalability. Here, a facile and high‐efficient synthesis is reported of WO 3 nanosheets based on the synergistic intercalation and oxidation of layered tungsten disulfide (WS 2 ). The complete conversion from WS 2 to WO 3 is confirmed by crystallographic, spectroscopic, microscopic, and elemental analysis. The prepared WO 3 nanosheets exhibit a superior specific capacitance of 480 F g −1 at a current density of 1 A g −1 and a good cycling stability at a current density of 10 A g −1 . Notably, benefitting from the 2D nanosheet structure and the high lattice symmetry, the cubic WO 3 nanosheets possess a high specific capacitance of 384 F g −1 at a high current density of 20 A g −1 , which is much higher than that of other WO 3 ‐based electrode materials.