YS-TaS2and YxLa1- xS-TaS2(0 ≤ x ≤ 1) Nanotubes: A Family of Misfit Layered Compounds

Abstract

We present the analysis of a family of nanotubes (NTs) based on the quaternary misfit layered compound (MLC) YxLa1-xS-TaS2. The NTs were successfully synthesized within the whole range of possible compositions via the chemical vapor transport technique. In-depth analysis of the NTs using electron microscopy and spectroscopy proves the in-phase (partial) substitution of La by Y in the (La,Y)S subsystem and reveals structural changes compared to the previously reported LaS-TaS2 MLC-NTs. The observed structure can be linked to the slightly different lattice parameters of LaS and YS. Raman spectroscopy and infrared transmission measurements reveal the tunability of the plasmonic and vibrational properties. Density-functional theory calculations showed that the YxLa1-xS-TaS2 MLCs are stable in all compositions. Moreover, the calculations indicated that substitution of La by Sc atoms is electronically not favorable, which explains our failed attempt to synthesize these MLC and NTs thereof. © 2020 American Chemical Society. ; Israel Science Foundation, ISF: 7130970101 ; Center for Nanoscale Science and Technology, CNST: 43535000350000 ; 823717 ; Deutsche Forschungsgemeinschaft, DFG: HE 7675/1-1 ; University of the East, UE ; Ministerio de Economía y Competitividad, MINECO: MAT2016-79776-P ; A.E. acknowledges the support by Act 211 Government of the Russian Federation, Contract No. 02.A03.21.0006. The support of the Israel Science Foundation (Grant No. 7130970101), Irving and Cherna Moskowitz Center for Nano and Bio-Nano Imaging, and the Perlman Family Foundation and the Kimmel Center for Nanoscale Science (Grant No. 43535000350000) is greatly acknowledged. The HRSTEM and EELS studies as well as some of the ED and TEM investigations were conducted at the Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Spain. We thank G. Antorrena and L. Casado (LMA-INA) for their help with the XRD acquisition and the electrical measurements, respectively. R.A. gratefully acknowledges the support from the Spanish Ministry of Economy and Competitiveness (MINECO) through Project Grant MAT2016-79776-P (AEI/FEDER, UE) and from the European Union H2020 program "ESTEEM3" (823717). S.H. acknowledges funding by the German Research Foundation (HE 7675/1-1). I.P. is the incumbent of the Sharon Zuckerman Research Fellow Chair.