Effects of lithium impurities on electronic and optical properties of graphene nanoflakes: A DFT–TDDFT study

Ajeel, Fouad N.; Mohammed, Mohammed H.; Khudhair, Alaa M.

doi:10.1016/j.cjph.2019.01.009

Cited by 15 publications

(5 citation statements)

References 44 publications

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“…Both geometry optimization and excited state calculations of GQDs have been performed with Gaussian16 by using the hybrid functional B3LYP with the basis set 6-31G(d). Past studies show that the model B3LYP/6-31G(d) strikes the best balance between computational cost and accuracy [14,20,[28][29][30] Water has been chosen as the solvent and it has been incorporated in the calculations via polarizable continuum model (PCM) during both geometry optimization and excited state calculations. During the optimization evaluations, we also calculated the vibrational frequencies to ensure the system is truly at the minimum of the potential energy surface.…”

Section: Computational Detailsmentioning

confidence: 99%

Doped Graphene Quantum Dots UV-Vis Absorption Spectrum: A high-throughput TDDFT study

Özönder¹,

Ünlü²,

Güleryüz³

et al. 2022

Preprint

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We report on time-dependent density functional theory (TDDFT) calculations of the excited states of 63 different graphene quantum dots (GQDs) in square shape with side lengths 1 nm, 1.5 nm and 2 nm. We investigate the systematics and trends in the UV-Vis absorption spectra of these GQDs, which are doped with elements B, N, O, S and P at dopant percentages 1.5%, 3%, 5% and 7%. The results show how the peaks in the UV and visible parts of the spectrum as well as the total absorption evolve in the chemical parameter space along the coordinates of size, dopant type and dopant percentage. The absorption spectra calculated here can be used to obtain particular GQD mixture proportions that would yield a desired absorption profile such as flat absorption across the whole visible spectrum or one that is locally peaked around a chosen wavelength.

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Section: Computational Detailsmentioning

confidence: 99%

Doped Graphene Quantum Dots UV-Vis Absorption Spectrum: A high-throughput TDDFT study

Özönder¹,

Ünlü²,

Güleryüz³

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Past studies show that the model B3LYP/6-31G(d) strikes the best balance between computational cost and accuracy. 14 , 20 , 28 − 30 …”

Section: Computational Detailsmentioning

confidence: 99%

“…Both geometry optimization and excited-state calculations of GQDs have been performed with Gaussian16 by using the hybrid functional B3LYP with the basis set 6-31G(d). Past studies show that the model B3LYP/6-31G(d) strikes the best balance between computational cost and accuracy. ,,− …”

Section: Computational Detailsmentioning

confidence: 99%

Doped Graphene Quantum Dots UV–vis Absorption Spectrum: A High-Throughput TDDFT Study

et al. 2023

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We report on time-dependent density functional theory calculations of the excited states of 63 different graphene quantum dots (GQDs) in square shape with side lengths of 1, 1.5, and 2 nm. We investigate the systematics and trends in the UV–vis absorption spectra of these GQDs, which are doped with elements B, N, O, S, and P at dopant percentages of 1.5%, 3%, 5%, and 7%. The results show how the peaks in the UV and visible parts of the spectrum as well as the total absorption evolve in the chemical parameter space along the coordinates of size, dopant type, and dopant percentage. The absorption spectra calculated here can be used to obtain particular GQD mixture proportions that would yield a desired absorption profile such as flat absorption across the whole visible spectrum or one that is locally peaked around a chosen wavelength.

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“…Carbon-based materials, silicon-based materials, transition-metal oxides, and lithium-alloyed metals have been progressively used for negative electrodes for LIBs because of their higher specific charges and higher negative electrode potentials. − To stabilize the alkali metal anodes, carbon materials such as graphene, polycyclic aromatic hydrocarbons (PAHs), carbon nanotubes, and carbon nanofibers are widely employed as conductive matrices. − The high electrical conductivity, good structural stability, tunable surface functionality, and excellent mechanical properties of the carbon materials provide lithium batteries a better performance. The interaction of Li on graphene nanoflakes alters their optical properties as significant changes in the HOMO–LUMO gap occur depending on the position of the Li atom within the nanoflakes . The ionic bonding between the lithium atom and carbon is considered to describe effectively the interaction between Li and carbon in the sp 2 carbon system and the charge transfer controls the interaction of the Li–carbon nanostructure …”

Section: Introductionmentioning

confidence: 99%

“…The interaction of Li on graphene nanoflakes alters their optical properties as significant changes in the HOMO−LUMO gap occur depending on the position of the Li atom within the nanoflakes. 24 The ionic bonding between the lithium atom and carbon is considered to describe effectively the interaction between Li and carbon in the sp 2 carbon system and the charge transfer controls the interaction of the Li−carbon nanostructure. 25 PAHs are aromatic hydrocarbons having two or more fused benzene rings.…”

Section: ■ Introductionmentioning

confidence: 99%

Polycyclic Aromatic Hydrocarbons as Anode Materials in Lithium-Ion Batteries: A DFT Study

Ramya

Suresh

2023

J. Phys. Chem. A

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The structure and energetics of the interactive behavior of Li + and Li with polycyclic aromatic hydrocarbons (PAHs) have been studied at the wB97XD/6-311G(d,p) level of DFT. The electron distribution in the PAHs, analyzed using the topology of the molecular electrostatic potential (MESP), led to the categorization of their aromatic rings into five types, viz R s , R n , R d , R b , and R e . Among the different rings, sextet-type R s and naphthalene-type R n rings showed the highest interaction with Li + . The change in MESP at the nucleus of Li + (ΔV Li + ) due to the formation of the complex Li + ...PAH is found to be proportional to the adsorption energy (E 1 ). In Li...PAH, the spin density on Li is close to zero, suggesting the formation of Li + ...PAH •− due to the electron transfer from Li to PAH. The adsorption energy (E 2 ) for Li...PAH does not correlate with the change in MESP at the nucleus of Li, whereas the dissociation energy (E 3 ) of Li + ...PAH •− to yield Li + and PAH •− correlates well with the MESP data, ΔV Li . The study confirms that the change in MESP at the nucleus of Li + due to complex formation gives a quantitative measure of the electronic effect of the cation−π binding. The cell potential (V cell ) is predicted for the lithium ion battery (LIB) using the Li + ...PAH and Li...PAH adsorption energies. On the basis of the V cell data, "carbon nanoflake"-type systems, viz coronene, circumbiphenyl, C 42 H 16 , and C 50 H 18 are suggested as good anode materials for LIBs.

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Effects of lithium impurities on electronic and optical properties of graphene nanoflakes: A DFT–TDDFT study

Cited by 15 publications

References 44 publications

Doped Graphene Quantum Dots UV-Vis Absorption Spectrum: A high-throughput TDDFT study

Doped Graphene Quantum Dots UV-Vis Absorption Spectrum: A high-throughput TDDFT study

Doped Graphene Quantum Dots UV–vis Absorption Spectrum: A High-Throughput TDDFT Study

Polycyclic Aromatic Hydrocarbons as Anode Materials in Lithium-Ion Batteries: A DFT Study

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