skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Electronic and Thermoelectric Properties of Crystalline 2D Metal-Organic Framweorks.

Abstract

Abstract not provided.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1429759
Report Number(s):
SAND2017-3736J
652345
DOE Contract Number:
AC04-94AL85000
Resource Type:
Program Document
Country of Publication:
United States
Language:
English

Citation Formats

He, Yuping, He, Yuping, Spataru, Dan Catalin, Leonard, Francois Leonard, Jones, Reese E., Foster, Michael E., Allendorf, Mark D., and Talin, Albert Alec. Electronic and Thermoelectric Properties of Crystalline 2D Metal-Organic Framweorks.. United States: N. p., 2017. Web.
He, Yuping, He, Yuping, Spataru, Dan Catalin, Leonard, Francois Leonard, Jones, Reese E., Foster, Michael E., Allendorf, Mark D., & Talin, Albert Alec. Electronic and Thermoelectric Properties of Crystalline 2D Metal-Organic Framweorks.. United States.
He, Yuping, He, Yuping, Spataru, Dan Catalin, Leonard, Francois Leonard, Jones, Reese E., Foster, Michael E., Allendorf, Mark D., and Talin, Albert Alec. Sat . "Electronic and Thermoelectric Properties of Crystalline 2D Metal-Organic Framweorks.". United States. doi:.
@article{osti_1429759,
title = {Electronic and Thermoelectric Properties of Crystalline 2D Metal-Organic Framweorks.},
author = {He, Yuping and He, Yuping and Spataru, Dan Catalin and Leonard, Francois Leonard and Jones, Reese E. and Foster, Michael E. and Allendorf, Mark D. and Talin, Albert Alec},
abstractNote = {Abstract not provided.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}

Program Document:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that may hold this item.

Save / Share:
  • Topological crystalline insulator (TCI), Pb{sub 0.6}Sn{sub 0.4}Te, exhibits metallic surface states protected by crystal mirror symmetry with negligibly small band gap. Enhancement of its thermoelectric performances needs tuning of its electronic structure particularly through engineering of its band gap. While physical perturbations tune the electronic structure of TCI by breaking of the crystal mirror symmetry, chemical means such as doping have been more attractive recently as they result in better thermoelectric performance in TCIs. Here, we demonstrate that K doping in TCI, Pb{sub 0.6}Sn{sub 0.4}Te, breaks the crystal mirror symmetry locally and widens electronic band gap, which is confirmed bymore » direct electronic absorption spectroscopy and electronic structure calculations. K doping in Pb{sub 0.6}Sn{sub 0.4}Te increases p-type carrier concentration and suppresses the bipolar conduction via widening a band gap, which collectively boosts the thermoelectric figure of merit (ZT) to 1 at 708 K.« less
  • Control of the electronic properties of 2D transition material carbides by replacing the outer Ti layers in Ti 3C 2T xwith Mo, creating Mo 2TiC 2T x.
  • In this paper, a transition from metallic to semiconducting-like behavior has been demonstrated in two-dimensional (2D) transition metal carbides by replacing titanium with molybdenum in the outer transition metal (M) layers of M 3C 2 and M 4C 3 MXenes. The MXene structure consists of n + 1 layers of near-close packed M layers with C or N occupying the octahedral site between them in an [MX] nM arrangement. Recently, two new families of ordered 2D double transition metal carbides MXenes were discovered, M' 2M"C 2 and M' 2M" 2C 3 – where M' and M" are two different earlymore » transition metals, such as Mo, Cr, Ta, Nb, V, and Ti. The M' atoms only occupy the outer layers and the M" atoms fill the middle layers. In other words, M' atomic layers sandwich the middle M"–C layers. Using X-ray atomic pair distribution function (PDF) analysis on Mo 2TiC 2 and Mo 2Ti 2C 3 MXenes, we present the first quantitative analysis of structures of these novel materials and experimentally confirm that Mo atoms are in the outer layers of the [MC] nM structures. The electronic properties of these Mo-containing MXenes are compared with their Ti 3C 2 counterparts, and are found to be no longer metallic-like conductors; instead the resistance increases mildly with decreasing temperatures. Density functional theory (DFT) calculations suggest that OH terminated Mo–Ti MXenes are semiconductors with narrow band gaps. Measurements of the temperature dependencies of conductivities and magnetoresistances have confirmed that Mo 2TiC 2T x exhibits semiconductor-like transport behavior, while Ti 3C 2T x is a metal. Finally, this finding opens new avenues for the control of the electronic and optical applications of MXenes and for exploring new applications, in which semiconducting properties are required.« less