Controlled Synthesis of Compositionally Tunable Ternary PbSe_xS_1–xas Well as Binary PbSe and PbS Nanowires

Abstract

High-quality compositionally tunable ternary PbSe(x)S(1-x) (x = 0.23, 0.39, 0.49, 0.68, and 0.90) nanowires (NWs) and their binary analogues have been grown using solution-liquid-solid growth with lead(II) diethyldithiocarbamate, Pb(S(2)CNEt(2))(2), and lead(II) imido(bis(selenodiisopropylphosphinate)), Pb((SeP(i)Pr(2))(2)N)(2), as single-source precursors. The alloyed nature of PbSe(x)S(1-x) wires was confirmed using ensemble X-ray diffraction and energy dispersive X-ray spectroscopy (EDXS). Single NW EDXS line scans taken along the length of individual wires show no compositional gradients. NW compositions were independently confirmed using inductively coupled plasma atomic emission spectroscopy. Slight stoichiometric deviations occur but never exceed 13.3% of the expected composition, based on the amount of introduced precursor. In all cases, resulting nanowires have been characterized using transmission electron microscopy. Mean diameters are between 9 and 15 nm with accompanying lengths that range from 4 to 10 μm. Associated selected area electron diffraction patterns indicate that the PbSe(x)S(1-x), PbSe, and PbS NWs all possess the same <002> growth direction, with diffraction patterns consistent with an underlying rock salt crystal structure.

Cu2S/ZnS Heterostructured Nanorods: Cation Exchange vs. Solution–Liquid–Solid‐like Growth

“…The emergence of semiconductor nanocrystal (NC) heterostructures of anisotropic shapes that bring together different compositions and functionalities with directionality is creating new paths to advanced technologies . Among them, type II heterostructures with staggered band offsets are gaining much interest due to their ability to efficiently separate photoinduced charges, a salient feature useful in a variety of applications such as photovoltaics, photocatalysis, biomedical sensing, photothermal therapy, and optoelectronics .…”

Synthesis and Application of Solution-Based II–VI and IV–VI Semiconductor Nanowires

“…Thus, to overcome this problem, single source precursors, where both metal and chalcogen exist within the same compound, have been employed. Specifically, Sun et [46]. In the latter study, resulting PbS and PbSe NWs possess a mean diameter of 9 nm with lengths exceeding 10 µm.…”

“…This core can subsequently lock the two arms into place along its unique crystallographic directions. For II-VI NWs such as CdSe and CdTe, a ZB core can thus unite two wires with orientations along The flexibility of SLS growth enables not only II-VI but also IV-VI NWs to be synthesized [43][44][45][46]. Specifically, crystalline PbS and PbSe NWs have been made using Bi and Au/Bi NP seeded growth in tandem with lead oleate/TOPS [44] and lead acetate/TOPSe [43] precursor pairs.…”

“…They are synthesized in an analogous manner to binary PbS and PbSe NWs through the decomposition of both Pb((SeP i Pr 2 ) 2 N) 2 and (Pb (S 2 CNEt 2 ) 2 in the presence of BiCl 3 [46]. Of note is that the NW composition can readily be tuned by varying the mole ratio of these two precursors.…”

“…Specifically, because of the nature of the band offsets, carriers of one type are forced to stay in [46]. Copyright 2012 American Chemical Society the core while carriers of the other type experience favorable charge transfer into the shell.…”