Sol-gel synthesis of metal (V, W, Zn) oxide - Carbon nanocomposites as cathode materials for Al-ion batteries

In the future, Al-ion electrochemical cells seem to be a promising alternative for Li-ion batteries, due to their higher theoretical capacity, much lower toxicity and lower cost. Current work is related to this field of study and the comparison of different cathode materials based on V2O5, WO3, and ZnO synthesized using the sol-gel method for construction of Al-ion cells was presented. The physicochemical properties of obtained amorphous and crystalline materials, both, single-phase or composite MOx/C materials were investigated using Differential Thermal Analysis and Thermogravimetry combined with Mass Spectrometry (DTA - TG - MS), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Electrochemical Impedance Spectroscopy (EIS). Obtained composite metal oxide/carbon (MOx/C where MOx = WO3, V2O5, ZnO) materials were used as cathode materials in aluminum-ion batteries and the performance of such cells was determined. The results of electrochemical measurements were discussed in terms of the influence of different structure levels: crystallographic, electronic, nano- and microscopic on the cell properties. Although presented results did not allow to propose the complete description of the working mechanism of the investigated Al-ion cells, the presented interpretation and discussion led to some conclusions and showed the direction for future development of Al-ion cells.