Morphology-Controlled Vapor Phase Growth and Characterization of One-Dimensional GaTe Nanowires and Two-Dimensional Nanosheets for Potential Visible-Light Active Photocatalysts

Abstract

Gallium telluride (GaTe) one-dimensional (1D) and two-dimensional (2D) materials have drawn much attention for high-performance optoelectronic applications because it possesses a direct bandgap for all thickness. We report the morphology-controlled vapor phase growth of 1D GaTe nanowires and 2D GaTe nanosheets by a simple physical vapor transport (PVT) approach. The surface morphology, crystal structure, phonon vibration modes, and optical property of samples were characterized and studied. The growth temperature is a key synthetic factor to control sample morphology. The 1D GaTe single crystal monoclinic nanowires were synthesized at 550 °C. The strong interlayer interaction and high surface migration of adatoms on c-sapphire enable the assembly of 1D nanowires into 2D nanosheet under 600 °C. Based on the characterization results demonstrated, we propose the van der Waals growth mechanism of 1D nanowires and 2D nanosheets. Moreover, the visible-light photocatalytic activity of 1D nanowires and 2D nanosheets was examined. Both 1D and 2D GaTe nanostructures exhibit visible-light active photocatalytic activity, suggesting that the GaTe nanostructures may be promising materials for visible light photocatalytic applications.