ALKALI METAL INTERCALATED 2D MATERIALS AND THEIR APPLICATIONS

Abstract

In this thesis, alkali metal intercalated 2D materials were extensively studied. The samples were prepared using commercially-available alkali metal salt precursors, which are easy to handle. Structural phase transitions were observed in numerous group 6 TMDCs, with better control over the intercalation process compared to traditional solution phase methods. Consequently, pure 2H to complete 1T’ phase conversion can be achieved in TMDCs. Additionally, a staging process for lithium intercalated BP was observed. With proper control over the lithium dose, quasi-few layer and monolayer BP can be obtained, evidenced by electron spectroscopy and photoluminescence. To overcome the stability issue of alkali metals, chemical passivation methods have been explored. Such methods are advantageous over physical encapsulation in terms of handling and scalability. The stability of alkali metal intercalated 2D materials was found to improve dramatically by hydrogenating the intercalated alkali metal to their hydride analogues.