Synthesis of Single-Crystalline Lead Sulfide Nanoframes and Nanorings

Abstract

We present a colloidal synthesis strategy to obtain single-crystalline PbS nanorings. By controlling the ripening process in the presence of halide ions, a transformation of initial PbS nanosheets to frame-like structures and finally to nanorings was achieved. We found that the competing ligands oleic acid, oleate and halide ions play an important role in the formation of these nanostructures. Therefore, we propose a formation mechanism based on a thermally induced ripening of crystal facets dependent on the surface passivation. With this method, it became possible to synthesize colloidal nanorings of cubic crystal phase galena PbS. The synthesis was followed via TEM and the products are characterized by XRD, AFM and STEM tomography. Control of the initial nanoframe morphology allows adjusting the later nanoring dimensions.

From CdSe Nanoplatelets to Quantum Rings by Thermochemical Edge Reconfiguration

“…We remark here that these shapes all belong to the genus = 0 class. Reports in the literature on the synthesis of colloidal quantum rings, i.e., with a genus of 1 topology, recently emerged. − …”

Single‐Crystalline Colloidal Quasi‐2D Tin Telluride

“…As known, halide ions released from halide alkanes are the actually functioning ligands instead of the original halide alkanes themselves in IV-VIA group semiconductors. [27] By means of the specific binding preference on crystal surfaces, or the complexation with metal atoms, or the etching process, halide ions have been proven as good optional ligands for obtaining 2D nanostructures in solution. [22,24,28] Further, we found that for the NS formation, halide ions can be introduced from salts such as LiCl or LiBr dissolved in dimethylformamide (DMF) and added to the reaction flask.…”

“…Note, the occurrence of the etching on SnTe is assumed to be mainly due to the change of the chemical environment when the tin chloride/bromide is used. [27] The salt addition into the reaction can affect the polarity of the solvent. Further, it also alters the capping conditions of the organic ligand layers on the crystal surface, which triggers the etching process when the ligand layer conditions change, followed by a change of the solubility of SnTe.…”

Nanoframes as a Resilient Candidate for a Broader Spectra of Catalysis Challenges

“…Elemental analysis was performed via energy-dispersive X-ray (EDX). Lead sulfide nanoframes can be synthesized by the one-pot synthesis method [52]. Lead acetate trihydrate, oleic acid, and diphenyl ether were all mixed in a round-bottomed flask and degassed at 7 • C for 2 h. During heating at 22 • C (lithium chloride dimethylformamide), LiCl-DMF solution was added.…”