Facile preparation of electrodes based on WO 3 nanostructures modified with C and S used as anode materials for Li‐ion batteries

Abstract An appropriate morphological and structure matrix configuration where lithium ions could insert and de‐insert is essential for lithium‐ion batteries (LiB). Tungsten oxides (WO 3 ) are especially attractive materials for this aim. In this research, the effects of the morphology and composition of WO 3 nanostructures on the charge/discharge behavior for Li‐ion batteries are methodically examined. On the one hand, nanostructured WO 3 thin film was effectively synthesized by an electrochemical procedure. Then, an annealing treatment at 600°C in air environment for 4 h was carried out. In the second electrode synthesized, a carbon layer was uniformly deposited on WO 3 nanostructures to obtain a WO 3 /C electrode. Finally, WO 3 /WS 2 electrodes were prepared by means of in situ sulfurization of WO 3 one‐step solid‐state synthesis using tungsten trioxide (WO 3 ) and thiourea as precursor material. By using X‐ray photoelectron spectroscopy, X‐ray diffraction analysis, transmission electron microscopy, Raman spectra, and field‐emission scanning electron microscopy, the three electrodes have been morphologically characterized. Electrochemical properties were analyzed by cyclic voltammogram, galvanostatic charge/discharge cycling, and electrochemical impedance spectroscopy. Among all the synthesized samples, WO 3 /C nanostructures reveal the best performance as they exhibit the greatest discharge capacity and cycle performance (820 mA h g −1 ).