二維過渡金屬二硫屬化物 能源轉換和存儲：密度 密度泛函理論研究

Abstract

In this dissertation, selected two-dimensional (2D) transition metal dichalchogenides (TMDs) were assessed with respect to their potential applications in energy conversion and storage via density functional theory (DFT) calculations and ab-initio random structure searching. It is found that: (1) single-layer Li-decorated MoS2to be able to bind sufficiently high enough H2 molecules for hydrogen storage applications,and that it can also serve as H2 dissociation catalyst with potential use in fuel cell technology; (2) A relatively new 2D TMD structural phase called 1T' was suggested to be the more relevant structure for hydrogen evolution reaction (HER). It is found that basal plane HER activity is present for 1T'-MX (M = Mo, W; X = S, Se, Te) materials, and that this can be further enhanced and tuned by utilizing tensile biaxial strain; and lastly, (3) the recently fabricated single-layer metallic VS2 was shown to be an excellent candidate as sodium-ion battery (NIB) anode due to its inherent conducting nature, very low Na ion diffusion barrier and high specific energy capacity for storing Na ions. These works also demonstrated the versatility of 2D TMDs in a wide range of applications, particularly in energy-related ones, by virtue of their chemical composition and structure.