Penta-C20: A Superhard Direct Band Gap Carbon Allotrope Composed of Carbon Pentagon

A metastable sp3-bonded carbon allotrope, Penta-C20, consisting entirely of carbon pentagons linked through bridge-like bonds, was proposed and studied in this work for the first time. Its structure, stability, and electronic and mechanical properties were investigated based on first-principles calculations. Penta-C20 is thermodynamically and mechanically stable, with equilibrium total energy of 0.718 and 0.184 eV/atom lower than those of the synthesized T-carbon and supercubane, respectively. Penta-C20 can also maintain dynamic stability under a high pressure of 100 GPa. Ab initio molecular dynamics (AIMD) simulations indicates that this new carbon allotrope can maintain thermal stability at 800 K. Its Young’s modulus exhibits mechanical anisotropy. The calculated ideal tensile and shear strengths confirmed that Penta-C20 is a superhard material with a promising application prospect. Furthermore, Penta-C20 is a direct band gap carbon based semiconducting material with band gap of 2.89 eV.

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Direct band gap nature and optical response of BexMgyZn1−(x+y)Se

Modern Physics Letters B ◽

10.1142/s021798491650007x ◽

2016 ◽

Vol 30 (03) ◽

pp. 1650007

Author(s):

Naeemullah ◽

G. Murtaza ◽

R. Khenata ◽

S. Bin Omran

Keyword(s):

Band Gap ◽

First Principles ◽

Density Functional ◽

Experimental Measurements ◽

First Principles Calculations ◽

Functional Theory ◽

Direct Band Gap ◽

Direct Band ◽

First Time ◽

Ultraviolet Energy

For the first time, the electronic and optical properties of the quaternary Be[Formula: see text]Mg[Formula: see text]Zn[Formula: see text]Se alloy have been investigated using first-principles calculations within the framework of density functional theory (DFT). Variations in the direct band gap with the change in [Formula: see text] and [Formula: see text] compositions show agreement with the experimental measurements. Evaluation of the dielectric function and refractive index reveals the optical activity in the visible and ultraviolet energy regions.

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Strain-induced semimetal-to-semiconductor transition and indirect-to-direct band gap transition in monolayer 1T-TiS2

RSC Advances ◽

10.1039/c5ra16877e ◽

2015 ◽

Vol 5 (102) ◽

pp. 83876-83879 ◽

Cited By ~ 23

Author(s):

Chengyong Xu ◽

Paul A. Brown ◽

Kevin L. Shuford

Keyword(s):

Band Gap ◽

Electronic Properties ◽

Plane Strain ◽

Material Properties ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Direct Band ◽

Uniform Plane

We have investigated the effect of uniform plane strain on the electronic properties of monolayer 1T-TiS2using first-principles calculations. With the appropriate tensile strain, the material properties can be transformed from a semimetal to a direct band gap semiconductor.

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First principles study of silicene symmetrically and asymmetrically functionalized with halogen atoms

RSC Advances ◽

10.1039/c6ra18179a ◽

2016 ◽

Vol 6 (98) ◽

pp. 95846-95854 ◽

Cited By ~ 25

Author(s):

Wencheng Tang ◽

Minglei Sun ◽

Qingqiang Ren ◽

Yajun Zhang ◽

Sake Wang ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Tensile Strain ◽

First Principles Calculations ◽

Direct Band Gap ◽

Halogen Atoms ◽

First Principles Study ◽

Direct Band

Using first principles calculations, we predicted that a direct-band-gap between 0.98 and 2.13 eV can be obtained in silicene by symmetrically and asymmetrically (Janus) functionalisation with halogen atoms and applying elastic tensile strain.

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Penta-MX2 (M = Ni, Pd and Pt; X = P and As) monolayers: direct band-gap semiconductors with high carrier mobility

Journal of Materials Chemistry C ◽

10.1039/c8tc06030d ◽

2019 ◽

Vol 7 (12) ◽

pp. 3569-3575 ◽

Cited By ~ 13

Author(s):

Shifeng Qian ◽

Xiaowei Sheng ◽

Xian Xu ◽

Yuxiang Wu ◽

Ning Lu ◽

...

Keyword(s):

Band Gap ◽

First Principles ◽

Carrier Mobility ◽

Two Dimensional ◽

First Principles Calculations ◽

Ring Network ◽

Direct Band Gap ◽

Direct Band ◽

High Carrier Mobility ◽

High Carrier

Two-dimensional binary MX2 (M = Ni, Pd and Pt; X = P and As) exhibiting a beautiful pentagonal ring network is discussed through first principles calculations.

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PBCF‐Graphene: A 2D Sp 2 Hybridized Honeycomb Carbon Allotrope with a Direct Band Gap

ChemNanoMat ◽

10.1002/cnma.201900645 ◽

2019 ◽

Vol 6 (1) ◽

pp. 139-147 ◽

Cited By ~ 21

Author(s):

Wei Zhang ◽

Changchun Chai ◽

Qingyang Fan ◽

Yanxing Song ◽

Yintang Yang

Keyword(s):

Band Gap ◽

Carbon Allotrope ◽

Direct Band Gap ◽

Direct Band

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Carbon nanotube: An indirect ~ 0 eV band gap material

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i5.321 ◽

2016 ◽

pp. 3546-3550

Author(s):

Maheshwar Sharon ◽

S. S. Kawale ◽

Rakesh Afre ◽

Madhuri Sharon ◽

C. H. Bhosale

Keyword(s):

Thin Film ◽

Carbon Nanotube ◽

Band Gap ◽

Carrier Concentration ◽

Hydrogen Atmosphere ◽

Sem Analysis ◽

Direct Band Gap ◽

Direct Band ◽

Indirect Band Gap ◽

First Time

Thin film of carbon was synthesized from camphor (C10H16O) by CVD technique in hydrogen atmosphere. For the first time it is confirmed the presence of almost zero indirect band gap in addition to its direct band gap.. Carrier concentration with intrinsic carbon is found to be around 1021 n/cm3. It is suggested that unless the zero indirect band gap is Â increased carbon thin film Â Â cannot be used for making a p:n junction. XRD, Raman and SEM analysis are performed.

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Indirect-to-direct band gap transition of the ZrS2 monolayer by strain: first-principles calculations

RSC Advances ◽

10.1039/c3ra46090h ◽

2014 ◽

Vol 4 (15) ◽

pp. 7396 ◽

Cited By ~ 62

Author(s):

Yan Li ◽

Jun Kang ◽

Jingbo Li

Keyword(s):

Band Gap ◽

First Principles ◽

First Principles Calculations ◽

Direct Band Gap ◽

Direct Band

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Phase stability, mechanical and optoelectronic properties of two novel phases of AlN

Modern Physics Letters B ◽

10.1142/s0217984917502013 ◽

2017 ◽

Vol 31 (18) ◽

pp. 1750201 ◽

Cited By ~ 11

Author(s):

Ruike Yang ◽

Chuanshuai Zhu ◽

Qun Wei ◽

Zheng Du

Keyword(s):

Band Gap ◽

First Principles ◽

Semiconductor Device ◽

Phonon Dispersion ◽

Ambient Pressure ◽

Optoelectronic Device ◽

First Principles Calculations ◽

Covalent Bonds ◽

Direct Band Gap ◽

Direct Band

Two novel aluminum nitride (which is bct-AlN at ambient pressure, and h-AlN at higher pressure) were predicted using first-principles calculations. The mechanical and phonon dispersion results indicate that bct-AlN is mechanically and dynamically stable at zero pressure, h-AlN phase can be stabilized by increasing pressure and it is mechanically and dynamically stable at 10 GPa. bct-AlN is more favorable than rs-AlN in thermodynamics at ambient pressure. Our calculated band gap of bct-AlN is 5.85 eV. It can be used as semiconductor device and optoelectronic device due to its inherent wide direct band gap. For bct-AlN, the shortest Al–N bond length is 1.8476 Å and its bond order index is 1.28, which shows that strong covalent bonds are formed between Al atoms and N atoms. Moreover, the anisotropy of Young’s modulus and optical properties can be noticed obviously for bct-AlN.

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Indirect-Direct Band Gap Transition by Van Der Waals Interaction Engineering in MoS2/WS2 Bilayer Heterojunction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.614.70 ◽

2014 ◽

Vol 614 ◽

pp. 70-74 ◽

Cited By ~ 2

Author(s):

Hai Ning Cao ◽

Zhi Ya Zhang ◽

Ming Su Si ◽

Feng Zhang ◽

Yu Hua Wang

Keyword(s):

Band Gap ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Direct Band Gap ◽

The Density Functional Theory ◽

Direct Band ◽

Electric Filed

First principles calculations based on the density functional theory (DFT) are employed to estimate the electronic structures of bilayer heterostructure of MoS2/WS2. The dependences of the band structures on external electric field and interlayer separation are evaluated. The external electric filed induces a semiconductor-metal transition. At the same time, a larger interlayer separation, corresponding to a weaker interlayer interaction, makes an indirect-direct band gap transition happen for the heterojunction. Our results demonstrate that electronic structure tailoring of two-dimensional layered materials should include both spatial symmetry control and interlayer vdW interactions engineering.

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