Density Functional Theory Study on Mechanism of Mercury Removal by CeO2 Modified Activated Carbon

Doping of CeO2 on activated carbon (AC) can promote its performance for mercury abatement in flue gas, while the Hg0 removal mechanism on the AC surface has been rarely reported. In this research, density functional theory (DFT) calculations were implemented to unveil the mechanism of mercury removal on plain AC and CeO2 modified AC (CeO2-AC) sorbents. Calculation results indicate that Hg0, HCl, HgCl and HgCl2 are all chemisorbed on the adsorbent. Strong interaction and charge transfer are shown by partial density of states (PDOS) analysis of the Hg0 adsorption configuration. HCl, HgCl and HgCl2 can be dissociatively adsorbed on the AC model and subsequently generate HgCl or HgCl2 released to the gas phase. The adsorption energies of HgCl and HgCl2 on the CeO2-AC model are relatively high, indicating a great capacity for removing HgCl and HgCl2 in flue gas. DFT calculations suggest that AC sorbents exhibit a certain catalytic effect on mercury oxidation, the doping of CeO2 enhances the catalytic ability of Hg0 oxidation on the AC surface and the reactions follow the Langmuir–Hinshelwood mechanism.

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Phosphorus Substitution Preference in Ye’elimite: Experiments and Density Functional Theory Simulations

Materials ◽

10.3390/ma14195874 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5874

Author(s):

Jiuye Zhao ◽

Jiazhi Huang ◽

Chunyang Yu ◽

Chunyi Cui ◽

Jun Chang

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Interplanar Spacing ◽

Quantitative Phase Analysis ◽

Partial Density ◽

Elemental Distribution ◽

Functional Theory ◽

X Ray ◽

Crystal System ◽

Calculation Results

Density functional theory (DFT) simulation has been recently introduced to understand the doping behavior of impurities in clinker phases. P-doped ye’elimite, a typical doping clinker phase, tends to form when phosphogypsum is used to manufacture calcium sulfoaluminate cement (CSA) clinkers. However, the substitution mechanism of P has not been uncovered yet. In this study, the influence of different doping amounts of P on the crystalline and electronic structure of ye’elimite was investigated using backscattered scanning electron microscopy–energy X-ray dispersive spectroscopy, X-ray diffraction tests, Rietveld quantitative phase analysis, and DFT simulations. Furthermore, the substitution preference of P in ye’elimite was revealed. Our results showed that increasing the doping amount of P increased the impurity contents in CSA clinkers, transforming the ye’elimite crystal system from the orthorhombic to the cubic system and decreasing the interplanar spacing of ye’elimite. Based on the calculation results of the defect formation energies, additional energies were required for P atoms to substitute Ca/Al atoms compared with those required for P atoms to substitute S atoms in both orthorhombic and cubic systems of ye’elimite. Combined calculation results of the bond length–bond order and partial density of states showed that the doped P atoms preferably substituted S atoms; the second possible substituted atoms were Al atoms, while there was only a slight possibility for substitution of Ca atoms. The substitution of P atoms for S atoms can be verified based on the elemental distribution in P-doped ye’elimite and the increasing residual CaSO4 contents. The transition of the crystal system and a decrease in the interplanar spacing for ye’elimite can also prove that the substitution of P atoms for Al atoms occurred substantially.

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A DFT Investigation of the Adsorption of Phosphate Ions on Co- and Ni-Doped Graphene

NANO ◽

10.1142/s1793292021501058 ◽

2021 ◽

pp. 2150105

Author(s):

Yan Zhang ◽

Hong Zhang ◽

Tao Chen ◽

Zhiming Zhang ◽

Libao An

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Density Of States ◽

Density Functional ◽

Physical Adsorption ◽

Partial Density ◽

Functional Theory ◽

Phosphate Ions ◽

Doped Graphene ◽

Co Doped

In this study, the adsorption of PO[Formula: see text], HPO[Formula: see text], H2PO[Formula: see text] on intrinsic, Co-doped and Ni-doped graphene has been investigated through density functional theory (DFT) calculations. Computing of final adsorption distance, adsorption energy, electron density and partial density of states shows that the adsorption between intrinsic graphene and phosphate ions is weak, and it is only physical adsorption. However, doping graphene with Ni or Co greatly enhances its adsorption with phosphate ions and leads to chemisorption. Combined with the analysis on the variation in conductance, Ni-doped graphene is more sensitive to and thus a promising material for detecting phosphate ions.

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γ-Valerolactone-Introduced Controlled-Isomerization of Glucose for Lactic Acid Production over Sn-Beta Catalyst

Green Chemistry ◽

10.1039/d1gc00378j ◽

2021 ◽

Author(s):

Xinpeng Zhao ◽

Zhimin Zhou ◽

hu luo ◽

Yanfei Zhang ◽

Wang Liu ◽

...

Keyword(s):

Density Functional Theory ◽

Lactic Acid ◽

Dft Calculations ◽

Acid Production ◽

Density Functional ◽

Lactic Acid Production ◽

Hydrothermal Conversion ◽

Functional Theory ◽

Environment Friendly

Combined experiments and density functional theory (DFT) calculations provided insights into the role of the environment-friendly γ-valerolactone (GVL) as a solvent in the hydrothermal conversion of glucose into lactic acid...

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Mechanistic understanding of the Cu(i)-catalyzed domino reaction constructing 1-aryl-1,2,3-triazole from electron-rich aryl bromide, alkyne, and sodium azide: a DFT study

Catalysis Science & Technology ◽

10.1039/d1cy00123j ◽

2021 ◽

Author(s):

Hanlin Gan ◽

Liang Peng ◽

Feng Long Gu

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Sodium Azide ◽

Density Functional ◽

Dft Study ◽

Domino Reaction ◽

Aryl Bromide ◽

Functional Theory ◽

Mechanistic Understanding

The mechanism of the Cu(i)-catalyzed domino reaction furnishing 1-aryl-1,2,3-triazole assisted by CuI and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) is explored with density functional theory (DFT) calculations.

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Density functional theory (DFT) calculations of VI/V reduction potentials of uranyl coordination complexes in non-aqueous solutions

Physical Chemistry Chemical Physics ◽

10.1039/c8cp05412f ◽

2019 ◽

Vol 21 (6) ◽

pp. 3227-3241 ◽

Cited By ~ 1

Author(s):

Krishnamoorthy Arumugam ◽

Neil A. Burton

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Aqueous Solutions ◽

Density Functional ◽

Coordination Complexes ◽

Dft Study ◽

Redox Behavior ◽

Functional Theory ◽

Reduction Potentials ◽

Uranium Complexes

Of particular interest within the +6 uranium complexes is the linear uranyl(vi) cation and it forms numerous coordination complexes in solution and exhibits incongruent redox behavior depending on coordinating ligands. This DFT study predicts VI/V reduction potentials of a range of uranyl(vi) complexes in non-aqueous solutions within ∼0.10−0.20 eV of experiment.

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Iron(II) complexes of dimethyltriazacyclophane

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229618015255 ◽

2018 ◽

Vol 74 (12) ◽

pp. 1641-1649

Author(s):

Wei-Tsung Lee ◽

Matthias Zeller ◽

David Upp ◽

Yuliya Politanska ◽

Doug Steinman ◽

...

Keyword(s):

Density Functional Theory ◽

Solid State ◽

Dft Calculations ◽

Density Functional Calculations ◽

Density Functional ◽

Coordination Mode ◽

Functional Theory ◽

Metal Centers ◽

Bonding Interaction

Treatment of the ortho-triazacyclophane 1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-triene [(C6H5)3(NH)(NCH3)2, L1] with Fe[N(SiMe3)2]2 yields the dimeric iron(II) complex bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)bis[(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)iron(II)], [Fe(C20H18N3)4] or Fe2(L1)4 (9). Dissolution of 9 in tetrahydrofuran (THF) results in solvation by two THF ligands and the formation of a simpler monoiron complex, namely bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido-κN 7)bis(tetrahydrofuran-κO)iron(II), [Fe(C20H18N3)2(C4H8O)2] or (L1)2Fe(THF)2 (10). The reaction is reversible and 10 reverts in vacuo to diiron complex 9. In the structures of both 9 and 10, the monoanionic triazacyclophane ligand L1− is observed in only the less-symmetric saddle conformation. No bowl-shaped crown conformers are observed in the solid state, thus preventing chelating κ3-coordination to the metal as had been proposed earlier based on density functional theory (DFT) calculations. Instead, the L1− ligands are bound in either a η2-chelating fashion through the amide and one amine donor (for one of the four ligands of 9), or solely through their amide N atoms in an even simpler monodentate η1-coordination mode. Density functional calculations on dimer 9 revealed nearly full cationic charges on each Fe atom and no bonding interaction between the two metal centers, consistent with the relatively long Fe...Fe distance of 2.912 (1) Å observed in the solid state.

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Synthesis, characterization, crystal structure and density functional theory (DFT) calculations of dioxomolybdenum (VI) complexes of an ONS donor ligand derived from benzoylacetone and S-benzyl dithiocarbazate

Polyhedron ◽

10.1016/j.poly.2012.12.006 ◽

2013 ◽

Vol 50 (1) ◽

pp. 602-611 ◽

Cited By ~ 9

Author(s):

Manashi Chakraborty ◽

Sathi Roychowdhury ◽

Nikhil Ranjan Pramanik ◽

Tapas Kumar Raychaudhuri ◽

Tapan Kumar Mondal ◽

...

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Functional Theory ◽

Donor Ligand

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The Pivotal Alkyne Group in the Mutual Size-Conversion of Au9 with Au10 Nanoclusters

Dalton Transactions ◽

10.1039/d1dt01586a ◽

2021 ◽

Author(s):

Xiaohang Wu ◽

Ying Lv ◽

Yuyuan Bai ◽

Haizhu Yu ◽

Manzhou Zhu

Keyword(s):

Density Functional Theory ◽

Theoretical Model ◽

Dft Calculations ◽

Density Functional ◽

Single Atom ◽

Functional Theory

Herein, density functional theory (DFT) calculations were performed to elucidate the mechanism of the reversible single atom size conversion between [Au10(DMPP)4(C6H11C≡C)]3+ and [Au9(DMPP)4]3+ (DMPP is 2,2’-bis-(dimethylphosphino)-1,1’-biphenyl, the simplified, theoretical model...

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Design and Prediction of High Potent ansa-Zirconocene for Olefin Polymerizations: Combined DFT Calculations and QSPR Approach

New Journal of Chemistry ◽

10.1039/d1nj00655j ◽

2021 ◽

Author(s):

Manussada Ratanasak ◽

Jun-ya Hasegawa ◽

Vudhichai Parasuk

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Functional Theory ◽

Olefin Polymerizations

Homopolymerization of ethene (ET), propene (PP), 1-butene (BT), 1-hexene (HX), and styrene (ST) by rac [Zr{1-Me2Si(3-Pr-(η5-C9H5))(3-H-(η5-C9H5))Cl2] ansa-zirconocene catalyst were investigated using Density Functional Theory (DFT) calculations. This study unveiled the...

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Iron Chelation by thiocytosine: Investigating electronic and structural features for describing tautomerism and metal chelation processes

Main Group Chemistry ◽

10.3233/mgc-210110 ◽

2021 ◽

pp. 1-8

Author(s):

Azadeh Jafari Rad ◽

Maryam Abbasi ◽

Bahareh Zohrevand

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Molecular Orbital ◽

Density Functional ◽

Biological Systems ◽

Iron Chelation ◽

Structural Features ◽

Metal Chelation ◽

Functional Theory

This work was performed regarding the importance of iron (Fe) chelation for biological systems. This goal was investigated by assistance of a model of thiocytosine (TC) for participating in Fe-chelation processes. First, formations of tautomeric conformations were investigated to explore existence of possible structures of TC. Next, Fe-chelation processes were examined for all four obtained tautomers of TC. The results indicated that thiol tautomers could be seen at higher stability than thio tautomers, in which one of such thiol tautomers yielded the strongest Fe-chelation process to build FeTC3 model. As a consequence, parallel to the results of original TC tautomers, Fe-chelated models were found to be achievable for meaningful chelation processes or sensing the existence of Fe in media. Examining molecular orbital features could help for sensing purposes. The results of this work were obtained by performing density functional theory (DFT) calculations proposing TC compounds suitable for Fe-chelation purposes.

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