Orthogonal PbS Nanowire Arrays and Networks and Their Raman Scattering Behavior

Abstract

Three-dimensional, orthogonal lead sulfide (PbS) nanowire arrays and networks have been prepared by using a simple, atmospheric pressure chemical vapor deposition (APCVD) method. These uniform nanowires (average diameter 30 nm) grow epitaxially from the surface of the initial PbS crystal seeds and form orthogonal arrays and networks in space. The growth mechanism has been explored, and the process was classified as homogeneous, epitaxial growth in the 200 directions. Furthermore, Raman spectra of PbS nanowires are reported here, and their characteristic Raman peak (190 cm(-1), no shoulder) could be used as a unique probe for the study of PbS nanomaterials.

Synthesis of metal sulfide nanomaterials via thermal decomposition of single-source precursors

“…Such branching growth mechanisms have been observed before in gas-phase synthesized PbS nanowire systems by Yang and coworkers 30 as well as Yi and coworkers. 31 Furthermore, we find that at lower precursor concentrations, nanowires exhibiting less branching and completely unbranched nanowires may be formed, due to the lack of additional precursor material to continue the branched nanowire growth. However, at these ratios of precursor to catalyst, the final chemical yield of nanowires is unsatisfactory.…”

Synthesis and Thermoelectrical Characterization of Lead Chalcogenide Nanowires

“…[17] A facile chemical vapor transport (CVT) synthesis of thin, highaspect ratio PbS nanowire arrays has also been reported. [18] This last method produces high-quality, single crystalline nanowires, highlighting CVT as a promising method for synthesis of PbX nanowires as novel TE materials.…”

“…2, left column) has been previously reported for PbS CVT nanowires and consists of a central cube with nanowires growing perpendicularly from each of the six faces. [18] In this case, Ge et al proposed a homogeneous, epitaxial growth process in which defects on the surfaces of the cubes serve as nucleation sites for the nanowire growth. The second type of array is selfsupporting and does not contain a central cube (Fig.…”

“…Several groups have previously reported amorphous silica coatings on CVT-synthesized PbS nanowires. [18,20] This silica most likely originates from etching of the silicon substrates and quartz reaction tube during the synthetic process. [21] Electronic properties of CVT-grown PbX nanowires were measured using contacts patterned by electron-beam lithography (EBL).…”

Hybrid Polyfluorene-Based Optoelectronic Devices

“…As shown in Figure 6, the recent evolution of the early hot-colloidal lead-salt nanocrystal synthesis has lead to more complex nanostructures including nanorods & nanowires (Acharya et al, 2008;Dom et al, 2009;Ge et al, 2005;Yong et al, 2006;F. Zhang & Wong, 2009), star-shaped nanocrystals (Lee et al, 2002;Zhu et al, 2007), nanocubes (Zhao & Qi, 2006), octahedral nanocrystals (Cho et al, 2005;Koh et al, 2010) and core-shell nanocrystals (Petryga et al, 2008;Stouwdam et al, 2007;Swart et al, 2010;Warner & Cao, 2008).…”