Spray deposition of 2D MoS${}_2$ and MXene (Ti${}_3$C${}_2$T${}_x$) nanosheets as anodes for Li and Na ion batteries

The current graphite- based anodes have a low capacity (372 mAh g${}^{-1}$) and unsatisfied rate capability, which leads to the current LIBs systems that struggle to meet the rapidly increasing energy consumption. As a result, the exploration and design of novel anode materials are extensively urgent. Two-dimensional (2D) molybdenum disulfide (MoS${}_2$), a typical material of layered transition metal dichalcogenides (TMDs), featuring with unique properties such as high specific area and short length of ion transfer due to the reduced dimension, are considered as a promising anode material for LIBs because of the high theoretical capacity (~ 670 mAh g${}^{-1}$) and large availability. Nonetheless, the commercial application of MoS${}_2$-based anodes has been restricted so far by the shortcomings of low electronic conductivity, and fast capacity degradation resulting from the inevitable volume expansion of the electrodes during the repetitive charge/discharge process. To this end, compositing MoS${}_2$-based electrodes with highly conductive and robust materials was proposed to solve the abovementioned issues. This thesis mainly focuses on the manufacture of 2D MoS${}_2$, Ti${}_3$C${}_2$T${}_x$ (MXene) electrodes, and their 2D heterostructures via a facile and scalable layer-by-layer (LBL) spray deposition technique, which is then used as anode materials for LIBs. More importantly, their lithium storage performance is intensively studied, including the corresponding reaction mechanism and the effect of various heterostructures and compositions, utilizing several ex-situ techniques such as Raman, SEM, XRD, and XPS.