Ultrathin Bi₂S₃ Nanowires: Surface and Core Structure at the Cluster-Nanocrystal Transition

Abstract

Herein, we present the structural characterization of the core and surface of colloidally stable ultrathin bismuth sulfide (Bi(2)S(3)) nanowires using X-ray Absorption Spectroscopy (EXAFS and XANES), X-ray Photoelectron Spectroscopy (XPS), and Nuclear Magnetic Resonance (NMR). These three techniques allowed the conclusive structural characterization of the inorganic core as well as the coordination chemistry of the surface ligands of these structures, despite the absence of significant translational periodicity dictated by their ultrathin diameter (1.6 nm) and their polycrystallinity. The atomic structure of the inorganic core is analogous to bulk bismuthinite, but Bi atoms display a remarkably higher coordination number than in the bulk. This can be only explained by a model in which each bismuth atom at the surface (or in close proximity to it) is bound to at least one ligand at any time.

A mild biomolecule-assisted route for preparation of flower-like AgBiS2 crystals

“…The two strong peaks at 158.09 and 163.35 eV Fig. 3(c) are attributed to Bi4f 7/2 and Bi 4f 5/2 , which is similar in the reference [27,28]. The S 2s core-level spectrum Fig.…”

Atomistic Modeling of Morphology and Electronic Properties of Colloidal Ultrathin Bi2S3 Nanowires

“…By first-principles calculations, we show that ultrathin NWs are stable against separation into isolated ribbons and that the stability increases with diameter d. For NWs with d < 2 nm, the cohesion of the NW is small yet sufficient to have stable NWs at room temperature, as reported in ref 49. Larger ultrathin crystalline NWs ( Figure 1) are obtained in the present work by a novel oleylamine-based organometallic synthesis employing bismuth acetate as precursor.…”

“…Surface passivation is typically obtained by oleic acid 22,31,48 and oleylamine, 36,39 two surfactants that bind to the nanocrystals with their polar head and expose their apolar alkyl tail toward the solvent. Previous experiments 49 show that full coverage of the NWs by means of oleylamine is possible.…”

Thermal Decomposition of Bismuth Oxysulfide from Photoelectric Bi2O2S to Superconducting Bi4O4S3

“…17,23 Figure 4b reveals that Bi 4f have two main peaks at 158.3 eV and 163.7eV with a peak split of 5.4eV from Bi 3+ 17. In addition, two shoulder peaks at 156.6 eV and 161.8 eV arising from the bonding energies of S 2p 24. Figure 4cindicates that O 1s has bonding energy at 530.1 eV and 531.9 eV with a peak split of 1.8 eV from O 1s 17.…”