UCLA

Single layer crystalline materials, often termed two-dimension (2D) materials, have quickly become a popular topic of research interest due to their extraordinary properties. The intrinsic electrical, mechanical, and optical properties of graphene were found to be remarkably distinct from graphite, its bulk counterpart. In conjunction with newfound processing techniques, there is renewed interest in elucidating the structure-property relationships of other 2D materials like the transition metal dichalcogenides (TMDCs). The energy storage capability of 2D nanoplatelets of TiS2 and MoS2 are studied here providing a contrast with investigations of corresponding bulk materials in the early 1970s. TiS2 was synthesized into nanoplatelets using a hot injection route which provided a capacity of ~143mAhg-1 from thin film electrodes as determined by cyclic voltammetry measurements. Phase identification using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy to complement the electrochemical performance and impurity identification is presented. MoS2 thick films were created using a sulfonation reaction of synthesized MoO2 and were found to have a capacity of 220mAhg-1 using galvanostatic cycling measurements. Energy and power densities of these TMDCs are presented and shown to exceed the performance of commercial electrochemical capacitors.