Synthesis and Thermal Properties of Solid-State Structural Isomers: Ordered Intergrowths of SnSe and MoSe2

A family of structural isomers [(SnSe)1.05] m (MoSe2) n were prepared using the modulated elemental reactant method by varying the layer sequence and layer thicknesses in the precursor. By varying the sequence of Sn–Se and Mo–Se layer pairs deposited and annealing the precursors to self-assemble the...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the American Chemical Society 2015-07, Vol.137 (27), p.8803-8809
Main Authors: Gunning, Noel S, Feser, Joseph, Beekman, Matt, Cahill, David G, Johnson, David C
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A family of structural isomers [(SnSe)1.05] m (MoSe2) n were prepared using the modulated elemental reactant method by varying the layer sequence and layer thicknesses in the precursor. By varying the sequence of Sn–Se and Mo–Se layer pairs deposited and annealing the precursors to self-assemble the targeted compound, all six possible isomers [(SnSe)1.05]4(MoSe2)4, [(SnSe)1.05]3(MoSe2)3[(SnSe)1.05]1(MoSe2)1, [(SnSe)1.05]3(MoSe2)2[(SnSe)1.05]1(MoSe2)2, [(SnSe)1.05]2(MoSe2)3[(SnSe)1.05]2(MoSe2)1, [(SnSe)1.05]2(MoSe2)1[(SnSe)1.05]1(MoSe2)2[(SnSe)1.05]1(MoSe2)1, and [(SnSe)1.05]2(MoSe2)2[(SnSe)1.05]1(MoSe2)1[(SnSe)1.05]1(MoSe2)1 were prepared. The structures were characterized by X-ray diffraction and electron microscopy which showed that all of the compounds have very similar c-axis lattice parameters and in-plane constituent lattice parameters yet distinct isomeric structures. These studies confirm that the structure, order, and thickness of the constituent layers match that of the precursors. The cross-plane thermal conductivity is found to be very low (∼0.08 Wm–1 K–1) and independent of the number of SnSe–MoSe2 interfaces within uncertainty. The poor thermal transport in these layered isomers is attributed to a large cross-plane thermal resistance created by SnSe–MoSe2 and MoSe2–MoSe2 turbostratically disordered van der Waals interfaces, the density of which has less variation among the different compounds than the SnSe–MoSe2 interface density alone.
ISSN:0002-7863
1520-5126
DOI:10.1021/jacs.5b04351