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

Title: Superhard Pseudocubic BC2N Superlattices

Abstract

No abstract prepared.

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
902864
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 1, 5 January 2007; Related Information: Article No. 015502
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; SUPERLATTICES; PHYSICS; NATIONAL RENEWABLE ENERGY LABORATORY; Basic Sciences

Citation Formats

Chen, S., Gong, X. G., and Wei, S.-H. Superhard Pseudocubic BC2N Superlattices. United States: N. p., 2007. Web.
Chen, S., Gong, X. G., & Wei, S.-H. Superhard Pseudocubic BC2N Superlattices. United States.
Chen, S., Gong, X. G., and Wei, S.-H. Fri . "Superhard Pseudocubic BC2N Superlattices". United States. doi:.
@article{osti_902864,
title = {Superhard Pseudocubic BC2N Superlattices},
author = {Chen, S. and Gong, X. G. and Wei, S.-H.},
abstractNote = {No abstract prepared.},
doi = {},
journal = {Physical Review Letters},
number = 1, 5 January 2007,
volume = 98,
place = {United States},
year = {Fri Jan 05 00:00:00 EST 2007},
month = {Fri Jan 05 00:00:00 EST 2007}
}
  • Superhard cubic boron-carbonitrides (c-BC2N) are studied with the use of the ab initio pseudopotential density functional method. The total energy, lattice constant, bulk and shear moduli, and electronic band structures as well as the electron density of states are calculated for all the possible c-BC2N structures in an eight-atom zinc-blende-structured cubic unit cell. The results obtained provide a plausible explanation for recent experimental observations as well as a possible path to synthesis of the materials.
  • No abstract prepared.
  • Using the first-principles band structure and total energy method, we have studied the general trend of physical properties of the BC{sub 2}N alloy as a function of atomic configurations. We found that the mechanical properties of the BC{sub 2}N alloy are basically determined by the bond components: structures with more C-C and B-N bonds have low energy, high density, and high bulk and shear moduli, which validates the so called the bond counting rule. We also show that the electronic and optical properties of the BC{sub 2}N alloy are more sensitive to the atomic configuration, thus could be used inmore » future experimental measurement to identify the atomic configuration of BC{sub 2}N samples. A strong internal electric field produced by the polar interfaces is observed in the long period BC{sub 2}N{sub n x n} (111) superlattices, which explains the significant band gap decrease as the period n increases.« less
  • Carbon is an attractive material for hydrogen adsorption, due to its light weight, variety of structures, and ability to both physisorb and chemisorb hydrogen. Recently, fully hydrogenated graphene layers ( graphane ) have been predicted to exist [J.O. Sofo et al., Phys. Rev. B 75, 15340 (2007)], and experimentally observed [D.C. Elias et al., Science 323, 610 (2009)]. In this work, we examine analogues of graphane, in particular BNH2 and BC2NH4. Unlike graphene, these materials have a band gap without hydrogenation. Our results indicate that the hydrogenation product of BN is metastable: the fully hydrogenated compound BNH2 is higher inmore » energy than hexagonal BN sheets plus H2 molecules, in sharp contrast with graphane. We find that BC2NH4 is energetically very close to hexagonal BC2N+2H2 molecules. Furthermore our examination of the relative binding strengths of rows of symmetry related hydrogen atoms on BC2NH4shows that this compound is marginally higher in energy than BC2NH2 plus an H2 molecule, with the hydrogen atoms in BC2NH2 absorbed on the carbon sites. These remaining hydrogen atoms are not as strongly bound as in graphane, indicating that the average hydrogen chemisorption energy is controllable by changing the carbon content in the B-C-N layer.« less