Growth, characterization, and photoelectric response properties of Bi/Bi<sub>2</sub>Se<sub>3</sub>/Se core-shell nanowires
Abstract
<p indent="0mm">Although Bi<sub>2</sub>Se<sub>3</sub> has drawn considerable attention due to the unique band structure and properties, one-dimensional core-shell nanostructures of Bi<sub>2</sub>Se<sub>3</sub> are rarely reported. In this work, novel Bi/Bi<sub>2</sub>Se<sub>3</sub>/Se core-shell heterostructure nanowires were synthesized via chemical vapor deposition (CVD) using an Au catalyst-assisted vapor-liquid-solid (VLS) mechanism. The structure of the nanowires was characterized by a Bi nanowire core, a single-crystalline Bi<sub>2</sub>Se<sub>3</sub> shell, and amorphous Se quantum dots from the inside out, which exhibited a unique core-shell structure and nanowire/quantum dots heterostructure with a high aspect ratio. The results indicated that the Au catalyst played a crucial role in the formation of the one-dimensional core-shell structure, while varied core-shell morphologies can be obtained via the vapor-solid (VS) mechanism without catalyst. The optoelectronic device based on an individual Bi/Bi<sub>2</sub>Se<sub>3</sub>/Se core-shell nanowire demonstrated that the heterointerface effectively enhanced photogenerated current and showed stable photoelectric response in the ultraviolet region, indicating promising potential for photodetection applications.</p>
