Synthesis and physical properties of cylindrite micro tubes and lamellae

Abstract

The natural semiconductor cylindrite FeSn 4 Pb 3 Sb 2 S 14 was synthesised by chemical vapour transport (CVT). Crystals with lamellar shape and cylindrical morphology could be deposited on substrates. The endothermic reactions responsible for material transport were simulated by means of thermodynamic modelling. Cylindrite belongs to the class of misfit layered compounds, where its modulated incommensurate crystal structure is based on the regular alternation of two types of layers. The so called T-and H-slab are incommensurately linked. Determined from single crystal XRD measurements, the modulation of atom positions as well as modulation of metal site occupancy of both subsystems are presented. The origin of super structure reflections found in scattering experiments can be clearly explained by a structure model. Based on experimentally determined single crystal XRD data and HRTEM inspections a model is derived to explain the formation of cylindrical architecture of crystals. The specific electrical conductivity of cylindrite improves from 10 TEM bright field image of high magnification demonstrating the continuous bending of (100) layers in a cylindrite cylinder.

Mechanical and liquid phase exfoliation of cylindrite: a natural van der Waals superlattice with intrinsic magnetic interactions

“…Interestingly, the growth conditions to reproduce the structure of cylindrite can be replicated in the laboratory to synthesize artificial crystals with cylindrite structure but with user-tailored composition. [41,42] Figure 1 shows a simplified representation of the crystal structure of cylindrite where for the sake of simplicity substitutional Fe, Sb and Sn atoms are not displayed. Figure 2a shows an optical image of cylindrite mineral displaying its characteristic appearance with clusters of small diameter (< 1 mm) and long (~ 3 -5 mm) cylinders.…”

“…This feature is originated by a phase segregation of the two crystalline phases during the rock formation. Interestingly, the growth conditions to reproduce the structure of cylindrite can be replicated in the laboratory to synthesize artificial crystals with cylindrite structure but with user-tailored composition [41,42]. Figure 1 shows a simplified representation of the crystal structure of cylindrite where for the sake of simplicity substitutional Fe, Sb and Sn atoms are not displayed.…”

First-Principles Study of a MoS2-PbS van der Waals Heterostructure Inspired by Naturally Occurring Merelaniite

“…The vdW heterostructures present unique electronic properties due to the incommensurate and modulating nature of their structural configurations along the crystallographic a - and b -directions. Despite their fascinating and attractive properties, only a few groups have so far succeeded in the synthesis of such heterostructures [ 11 , 12 , 13 , 14 , 15 , 16 , 17 ].…”

A Natural 2D Heterostructure [Pb3.1Sb0.9S4][AuxTe2–x] with Large Transverse Nonsaturating Negative Magnetoresistance and High Electron Mobility

“…The structure is composed of stacked, weakly coupled [Pb 2 BiS 3 ] layers and [AuTe 2 ] sheets. Magneto-transport measurements showed that [Pb 2 BiS 3 ]­[AuTe 2 ] is a multiband semimetal with strong spin–orbit coupling. , Actually, in nature, there are several other interesting 2D materials, such as the so-called cylindrite (FeSn 4 Pb 3 Sb 2 S 14 ), abramovite (Pb 2 SnInBiS 7 ), merelaniite (Mo 4 Pb 4 VSbS 15 ), levyclaudite (Pb 8 Sn 7 Cu 3 (Bi,Sb) 3 S 28 ), and jaszczakite ([(Pb,Bi) 3 S 3 ]­[AuS 2 ]), to name a few. Recently, it was demonstrated that the mineral franckeite can be exfoliated into a few layers toward efficient photodetectors .…”