Synthesis of Freestanding WS2 Trees and Fibers on Au by Chemical Vapor Deposition (CVD)

In this work, we report the synthesis of two new forms of WS2 nanostructures - freestanding WS2 trees and fibers on Au by chemical vapor deposition. It is observed that dislocation-driven growth causes WS2 crystals to grow and merge in both vertical and horizontal directions to form the pyramidal tree. During the formation of WS2 fibers, the presence of two-step growth was demonstrated. It is observed that sulphurization of WO3 nanoparticle leads to formation of WS2 rod in the first stage, followed by second stage in which selective growth causes some WS2 layers grow faster compared to other ones leading to the formation of fibrous WS2 structure. Fibers synthesized by our reported method have highly exposed WS2 layers which can demonstrate interesting catalytic and edge related properties or can be functionalized for future applications.