The Search for Molecular Corks Beyond Carbon Monoxide: A Quantum Mechanical Study of N-Heterocyclic Carbene Adsorption on Pd/Cu(111) and Pt/Cu(111) Single Atom Alloys

Heterocyclic Carbenes ◽

Binding Energies ◽

Single Atom ◽

Mechanical Study ◽

Quantum Mechanical Study ◽

Donor Ability ◽

Periodic Density Functional Theory calculations reveal the potential application of 10 imidazole based N-heterocyclic carbenes to behave as “molecular corks” for hydrogen storage on single atom alloys, comprised of Pd/Cu(111) or Pt/Cu(111). Calculations show that functionalizing the NHC with different electron withdrawing/donating functional groups results in different binding energies of the NHC with the alloy surfaces. The results are compared to DFT calculations of carbon monoxide bound to these alloys. The Huynh electronic parameter (is calculated for several simple imidazole NHCs to gauge σ-donor ability, while Se-NMR of and P-NMR calculations of selenourea derivatives and carbene-phosphinidene adducts, respectively, have been utilized to gauge π-acidity of the NHCs. It is demonstrated that consideration of both σ and π donating/accepting ability must be considered when predicting the surface-adsorbate binding energy. It was found that electron withdrawing groups tend to weaken the NHC-surface interaction while electron withdrawing substituents tend to strengthen the interaction.

The Search for Molecular Corks Beyond Carbon Monoxide: A Quantum Mechanical Study of N-Heterocyclic Carbene Adsorption on Pd/Cu(111) and Pt/Cu(111) Single Atom Alloys

JCIS Open ◽

10.1016/j.jciso.2021.100013 ◽

2021 ◽

pp. 100013

Author(s):

Scott Simpson

Keyword(s):

Carbon Monoxide ◽

Single Atom ◽

Quantum Mechanical ◽

Mechanical Study ◽

Quantum Mechanical Study ◽

High-Throughput Screening Single-Atom Alloy for Electroreduction of Dinitrogen to Ammonia

10.26434/chemrxiv.13546634 ◽

2021 ◽

Author(s):

Guokui Zheng ◽

Ziqi Tian ◽

Xingwang Zhang ◽

Liang Chen ◽

Xu Qian ◽

...

Keyword(s):

High Throughput Screening ◽

Density Functional ◽

Ammonia Synthesis ◽

Reduction Reaction ◽

Single Atom ◽

Functional Theory ◽

Metal Doped ◽

Single Atom Alloy ◽

Exploring electrocatalyst with high activity, selectivity and stability is essential for development of applicable electrocatalytic ammonia synthesis technology. By performing density functional theory calculations, we systematically investigated a series of transition-metal doped Au-based single atom alloys (SAAs) as promising electrocatalysts for nitrogen reduction reaction (NRR). For Au-based electrocatalyst, the first hydrogenation step (*N2→*NNH) normally determines the limiting potential of the overall reaction process. Compared with pristine Au(111) surface, introducing single atom can significantly enhance the binding strength of N2, leading to decreased energy barrier of the key step, i.e., ΔG(*N2→*NNH). According to simulation results, three descriptors were proposed to describe ΔG(*N2→*NNH), including ΔG(*NNH), d-band center, and . Eight doped elements (Ti, V, Nb, Ru, Ta, Os, W, and Mo) were initially screened out with limiting potential ranging from -0.75V to -0.30 V. Particularly, Mo- and W-doped systems possess the best activity with limiting potentials of -0.30 V, respectively. Then the intrinsic relationship between structure and the potential performance was further analyzed by using machine-learning. The selectivity, feasibility, stability of these candidates were also evaluated, confirming that SAA containing Mo, Ru ,Ta, and W could be outstanding NRR electrocatalysts. This work not only broadens the understating of SAA application in electrocatalysis, but also devotes to the discovery of novel NRR electrocatalysts.

The Molecular Adsorption of Carbon Monoxide on Cobalt Surfaces: A Dft Study

Progress in Reaction Kinetics and Mechanism ◽

10.3184/146867816x14799161258479 ◽

2017 ◽

Vol 42 (1) ◽

pp. 89-98 ◽

Cited By ~ 1

Author(s):

Fatemeh Borji ◽

Ali Nakhaei Pour ◽

Javad Karimi ◽

Mohammad Izadyar ◽

Zahra Keyvanloo ◽

...

Keyword(s):

Carbon Monoxide ◽

Density Functional ◽

Binding Energies ◽

Molecular Adsorption ◽

Cobalt Metal ◽

Total Density ◽

The Face ◽

Adsorption Energies ◽

Comparison Of The Results

The theoretical molecular adsorption energies, vibrational frequencies and total density of states of carbon monoxide (CO) on the (100), (110) and (111) surfaces of the face-centred cubic (FCC) crystalline phase of metallic cobalt were investigated using density functional theory calculations. The on-top adsorption state and three surface coverages were used for comparison of the results. The geometries of cobalt FCC surfaces, as well as those with adsorbed CO molecules and the CO binding energies were calculated with the generalised gradient approximation (GGA-D) using the revised revPBE-D3(BJ) functional. The theoretical results for adsorption energies of carbon monoxide were proportional to the electron density of the cobalt surfaces, according to the following order: FCC (100) > FCC (110) > FCC (111). For CO adsorbed on the surface of cobalt metal the C–O distance increases, producing a weakening of the bond and the calculated stretching frequency decreases when compared with the isolated molecule.

High-Throughput Screening Single-Atom Alloy for Electroreduction of Dinitrogen to Ammonia

10.26434/chemrxiv.13546634.v1 ◽

2021 ◽

Author(s):

Guokui Zheng ◽

Ziqi Tian ◽

Xingwang Zhang ◽

Liang Chen ◽

Xu Qian ◽

...

Keyword(s):

High Throughput Screening ◽

Density Functional ◽

Ammonia Synthesis ◽

Reduction Reaction ◽

Single Atom ◽

Functional Theory ◽

Metal Doped ◽

Single Atom Alloy ◽

Exploring electrocatalyst with high activity, selectivity and stability is essential for development of applicable electrocatalytic ammonia synthesis technology. By performing density functional theory calculations, we systematically investigated a series of transition-metal doped Au-based single atom alloys (SAAs) as promising electrocatalysts for nitrogen reduction reaction (NRR). For Au-based electrocatalyst, the first hydrogenation step (*N2→*NNH) normally determines the limiting potential of the overall reaction process. Compared with pristine Au(111) surface, introducing single atom can significantly enhance the binding strength of N2, leading to decreased energy barrier of the key step, i.e., ΔG(*N2→*NNH). According to simulation results, three descriptors were proposed to describe ΔG(*N2→*NNH), including ΔG(*NNH), d-band center, and . Eight doped elements (Ti, V, Nb, Ru, Ta, Os, W, and Mo) were initially screened out with limiting potential ranging from -0.75V to -0.30 V. Particularly, Mo- and W-doped systems possess the best activity with limiting potentials of -0.30 V, respectively. Then the intrinsic relationship between structure and the potential performance was further analyzed by using machine-learning. The selectivity, feasibility, stability of these candidates were also evaluated, confirming that SAA containing Mo, Ru ,Ta, and W could be outstanding NRR electrocatalysts. This work not only broadens the understating of SAA application in electrocatalysis, but also devotes to the discovery of novel NRR electrocatalysts.

Adenine as a Halogen Bond Acceptor: A Combined Experimental and DFT Study

Crystals ◽

10.3390/cryst9040224 ◽

2019 ◽

Vol 9 (4) ◽

pp. 224 ◽

Cited By ~ 7

Author(s):

Yannick Roselló ◽

Mónica Benito ◽

Elies Molins ◽

Miquel Barceló-Oliver ◽

Antonio Frontera

Keyword(s):

Density Functional ◽

Halogen Bond ◽

Lone Pair ◽

Halogen Bonding ◽

Functional Theory ◽

Adenine Ring ◽

Bonding Interaction ◽

Donor Ability ◽

Adenine Derivative

In this work, we report the cocrystallization of N9-ethyladenine with 1,2,4,5-tetrafluoro-3,6-diiodobenzene (TFDIB), a classical XB donor. As far as our knowledge extends, this is the first cocrystal reported to date where an adenine derivative acts as a halogen bond acceptor. In the solid state, each adenine ring forms two centrosymmetric H-bonded dimers: one using N1···HA6–N6 and the other N7···HB6–N6. Therefore, only N3 is available as a halogen bond acceptor that, indeed, establishes an N···I halogen bonding interaction with TFDIB. The H-bonded dimers and halogen bonds have been investigated via DFT (Density Functional Theory) calculations and the Bader’s Quantum Theory of Atoms In Molecules (QTAIM) method at the B3LYP/6-311+G* level of theory. The influence of H-bonding interactions on the lone pair donor ability of N3 has also been analyzed using the molecular electrostatic potential (MEP) surface calculations.

First-Principles Analysis on Interaction between Dopant (Ga, Sb) and Contamination Metal Atoms in Ge Crystals

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.205-206.417 ◽

2013 ◽

Vol 205-206 ◽

pp. 417-421

Author(s):

Tatsunori Yamato ◽

Koji Sueoka ◽

Takahiro Maeta

Keyword(s):

First Principles ◽

Density Functional ◽

Binding Energies ◽

Functional Theory ◽

Substitutional Site ◽

Metal Impurities ◽

Metal Atoms ◽

Total Energies ◽

Group 3

The lowest energetic configurations of metal impurities in 4throw (Sc - Zn), 5throw (Y - Cd) and 6throw (Hf - Hg) elements in Ge crystals were determined with density functional theory calculations. It was found that the substitutional site is the lowest energetic configuration for most of the calculated metals in Ge. The most stable configurations of dopant (Ga, Sb) - metal complexes in Ge crystals were also investigated. Following results were obtained. (1) For Ga dopant, 1st neighbor T-site is the most stable for metals in group 3 to 7 elements while substitutional site next to Ga atom is the most stable for metals in group 8 to 12 elements. (2) For Sb dopant, substitutional site next to Sb atom is the most stable for all calculated metals. Binding energies of the interstitial metalMiwith the substitutional dopantDswere obtained by the calculated total energies. The calculated results for Ge were compared with those for Si.

First-Principles DFT Insights into the Mechanisms of CO2 Reduction to CO on Fe (100)-Ni Bimetals

10.21203/rs.3.rs-540311/v1 ◽

2021 ◽

Author(s):

Caroline Kwawu ◽

Albert Aniagyei ◽

Destiny Konadu ◽

Elliot Menkah ◽

Richard Tia

Keyword(s):

Carbon Monoxide ◽

Binding Site ◽

Active Sites ◽

Density Functional ◽

Co2 Reduction ◽

Hydrocarbon Fuel ◽

Generalized Gradient ◽

Efficient Catalyst ◽

Stepped Surface

Abstract Iron and nickel are known active sites in the enzyme carbon monoxide dehydrogenases (CODH) which catalyzes CO2 to CO reversibly. The presence of nickel impurities in the earth abundant iron surface could provide a more efficient catalyst for CO2 degradation into CO, which is a feedstock for hydrocarbon fuel production. In the present study, we have employed spin-polarized dispersion-corrected density functional theory calculations within the generalized gradient approximation to elucidate the active sites on Fe (100)-Ni bimetals. We sort to ascertain the mechanism of CO2 dissociation to carbon monoxide on Ni deposited and alloyed surfaces at 0.25, 0.50 and 1 monolayer (ML) impurity concentrations. CO2 and (CO + O) bind exothermically i.e., -0.87 eV and − 1.51 eV respectively to the bare Fe (100) surface with a decomposition barrier of 0.53 eV. The presence of nickel generally lowers the amount of charge transferred to CO2 moiety. Generally, the binding strengths of CO2 were reduced on the modified surfaces and the extent of its activation was lowered. The barriers for CO2 dissociation increased mainly upon introduction of Ni impurities which is undesired. However, the 0.5 ML deposited (FeNi0.5(A)) surface is promising for CO2 decomposition, providing a lower energy barrier (of 0.32 eV) than the pristine Fe (100) surface. This active 1-dimensional defective FeNi0.5(A) surface provides a stepped surface and Ni-Ni bridge binding site for CO2 on Fe (100). Ni-Ni bridge site on Fe (100) is more effective for both CO2 binding or sequestration and dissociation compared to the stepped surface providing the Fe-Ni bridge binding site.

Two-dimensional metal-organic frameworks Mo3(C2O)12 as promising single-atom catalysts for selective nitrogen-to-ammonia

Journal of Materials Chemistry A ◽

10.1039/d1ta07613b ◽

2022 ◽

Author(s):

Zhen Feng ◽

Zelin Yang ◽

Xiaowen Meng ◽

Fachuang Li ◽

Zhanyong Guo ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Metal Organic Frameworks ◽

Reduction Reaction ◽

Single Atom ◽

Two Dimensional ◽

Functional Theory ◽

New Family ◽

Metal Organic

The development of single-atom catalysts (SACs) for electrocatalytic nitrogen reduction reaction (NRR) remains a great challenge. Using density functional theory calculations, we design a new family of two-dimensional metal-organic frameworks...