The First Template‐Free Growth of Crystalline Silicon Microtubes

Abstract

A simple template‐free high‐temperature evaporation method was developed for the growth of crystalline Si microtubes for the first time. As‐grown Si microtubes were characterized using X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and room‐temperature photoluminescence. The lengths of the Si tubes can reach several hundreds of micrometers; some of them have lengths on the order of millimeters. Each tube has a uniform outer diameter along its entire length, and the typical outer diameter is ≈ 2–3 μm. Most of the tubes have a wall thickness of ≈ 400–500 nm, though a considerable number of them exhibit a very thin wall thickness of ≈ 50 nm. Room‐temperature photoluminescence measurement shows the as‐synthesized Si microtubes have two strong emission peaks centered at ≈ 589 nm and ≈ 617 nm and a weak emission peak centered at ≈ 455 nm. A possible mechanism for the formation of these Si tubes is proposed. We believe that the present discovery of the crystalline Si microtubes will promote further experimental studies on their physical properties and smart applications.

Bandgap Modulation in BP Field Effect Transistor and Its Applications

“…Due to impurity energy levels, the bandgap of silicon becomes narrower and conductivity is enhanced. [ 88,89 ] Compared with Si, BP is a direct bandgap semiconductor. Doping occurs on the surface of a 2D material, and impurity atoms are combined with BP by dangling bonds.…”

Prospective important semiconducting nanotubes: synthesis, properties and applications

“…The PL intensities and the centers of the emission bands changed with decreasing size. Hu et al 95 presented a room-temperature PL spectrum of the Si microtubes. There were two strong peaks centered at $589 nm and $617 nm and a weak peak centered at $455 nm.…”

Mild hydrothermal preparation of a layered metal hydroxide salt with microtube/rod morphology

“…The discovery of carbon nanotubes represents a milestone in the exploration of low-dimensional materials and has stimulated great research interest in materials science (Collins, Zettl, Bando, Thess, & Smalley, 1997;Iijima, 1991;Lee et al, 2006;Li, Cao, Feng, & Li, 2004;Shim & Kotov, 2005). Inorganic WS 2 nanotubes have also been prepared, followed by the synthesis of a variety of other inorganic materials with one-dimensionality (Hu, Bando, Liu, Zhan, & Golberg, 2004;Remskar, 2004;Remskar et al, 1998;Tenne, Margulis, Genut, & Hodes, 1992). During the past decade, the synthetic approaches, the growth mechanism, and the physical and chemical properties (Hu et al, 1999) of inorganic rods (Cao et al, 2003), wires (Huynh, Dittmer, & Alivisatos, 2002;, ribbons (Yang, Wang, Zhang, & Liu, 2004), strands (Ichinose, Kurashima, & Kunitake, 2004) and tubes (Gao, Zhan, & Liu, 2006;Kang et al, 2003;Li, Wang, & Li, 2004), all of which possess one-dimensional features, have been extensively investigated.…”