scholarly journals Oxygen (O2) reduction reaction on Ba-doped LaMnO3 cathodes in solid oxide fuel cells: a density functional theory study

2021 ◽  
Vol 10 (4) ◽  
Author(s):  
Albert Aniagyei ◽  
Caroline Kwawu ◽  
Ralph Kwakye ◽  
Boniface Yeboah Antwi ◽  
Jonathan Osei-Owusu
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Oxygen Adsorption ◽  
Reduction Reaction ◽  
Functional Theory ◽  
Dissociation Energies ◽  
Gibbs Energies ◽  
O2 Reduction ◽  
Adsorption Energies ◽  
Cation Sites

AbstractThe oxygen adsorption and subsequent reduction on the {100} and {110} surfaces of 25% Ba-doped LaMnO3 (LBM25) have been studied at the density functional theory (DFT) with Hubbard correction and the results compared with adsorption on 25% Ca-doped LaMnO3 (LCM25) and Sr-doped LaMnO3 (LSM25). The trend in the reduction energies at the Mn cation sites are predicted to be in the order LSM25 < LBM25 < LCM25. In addition, the trend in dissociation energies for the most exothermic dissociated precursors follow the order LBM25 < LSM25 < LCM25. The adsorption energies (− 2.14 to − 2.41 eV) calculated for the molecular O2 precursors at the Mn cation sites of LCM25, LSM25 and LBM25 are thermodynamically stable, when compared directly with the adsorption energies (Eads = − 0.56 to − 1.67 eV) reported for the stable molecular O2 precursors on the Pt, Ni, Pd, Cu and Ir {111} surfaces. The predicted Gibbs energies as a function of temperature (T = 500–1100 °C) and pressures (p = 0.2 atm) for the adsorption and dissociation on the surfaces were negative, an indication of the feasibility of oxygen reduction reaction on the {100} and {110} surfaces at typical operating temperatures reported in this work.

scholarly journals Decoupling strain and ligand effects in ternary nanoparticles for improved ORR electrocatalysis

2016 ◽  
Vol 18 (35) ◽  
pp. 24737-24745 ◽  
Author(s):  
Paul C. Jennings ◽  
Steen Lysgaard ◽  
Heine A. Hansen ◽  
Tejs Vegge
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
Oxygen Reduction Reaction ◽  
Density Functional ◽  
Pt Nanoparticles ◽  
Reduction Reaction ◽  
Functional Theory ◽  
Transition Metal Nanoparticles ◽  
Ligand Effects ◽  
Adsorption Energies

Ternary Pt–Au–M (M = 3d transition metal) nanoparticles show reduced OH adsorption energies and improved activity for the oxygen reduction reaction (ORR) compared to pure Pt nanoparticles, as obtained by density functional theory.

Density-Functional Theory of O2 Physical Adsorption on sp3 and sp2 Hybridized Nitrogen-Doped CNT Surfaces for Fuel Cell Electrode

2011 ◽  
Vol 233-235 ◽  
pp. 17-22 ◽  
Author(s):  
Wong Wai Yin ◽  
Wan Ramli Wan Daud ◽  
Abu Bakar Mohamad ◽  
Abdul Amir Hassan Kadhum ◽  
Loh Kee Shyuan ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Fuel Cell ◽  
Density Functional ◽  
Physical Adsorption ◽  
Oxygen Adsorption ◽  
Reduction Reaction ◽  
Binding Energies ◽  
Metallic Behavior ◽  
Functional Theory ◽  
Nitrogen Doped

Catalysis is the major process involved in fuel cell technology to generate electricity which is known renewable. Generally, fuel cell electrodes utilize platinum supported carbon to catalyze the reactions at both cathode and anode. However, cheaper substitution materials such as nitrogen-doped carbon catalyst have attracted greater attention in recent year due to its significant catalytic activity at cathode in fuel cell. Nitrogen-doped CNT (N-CNT) is believed to allow oxygen reduction reaction (ORR) at cathode to take place which play a role as n-type dopant for electrical conductivity. The objective of this paper is to understand the mechanism of oxygen adsorption on N-CNT using the density-functional theory (DFT). N-CNT with two configurations involve sp2 and sp3 hybridized nitrogen are studied and compared in order to find the most thermodynamically stable N-CNT for sustainable ORR activity in fuel cell. The structural stability is studied through the binding energies of each configurations and the metallic behavior is examined through the energy gaps from the HOMO-LUMO studies. Finally, the adsorption energies and deformation energies of oxygen on N-CNT is discussed. Results revealed that sp3 hybridized N-CNT gives the most stable structure with compatible oxygen adsorption ability.

Computational study of oxygen adsorption in metal–organic frameworks with exposed cation sites: effect of framework metal ions

RSC Advances ◽  
2015 ◽  
Vol 5 (42) ◽  
pp. 33432-33437 ◽  
Author(s):  
Yong Wang ◽  
Jiangfeng Yang ◽  
Zhengjie Li ◽  
Zhuoming Zhang ◽  
Jinping Li ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Metal Ions ◽  
Density Functional ◽  
Computational Study ◽  
Metal Organic Frameworks ◽  
Oxygen Adsorption ◽  
Functional Theory ◽  
Metal Organic ◽  
Cation Sites

Using a dispersion-corrected density functional theory (DFT-D) method, this work shows that Ni3(BTC)2 can be potentially considered as promising adsorbent for O2/N2 separation with easier deoxygenation.

scholarly journals Probing the activity of transition metal M and heteroatom N4 co-doped in vacancy fullerene (M–N4–C64, M = Fe, Co, and Ni) towards the oxygen reduction reaction by density functional theory

RSC Advances ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 3174-3182
Author(s):  
Siwei Yang ◽  
Chaoyu Zhao ◽  
Ruxin Qu ◽  
Yaxuan Cheng ◽  
Huiling Liu ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Density Functional ◽  
Reduction Reaction ◽  
Functional Theory ◽  
Co Doped

In this study, a novel type oxygen reduction reaction (ORR) electrocatalyst is explored using density functional theory (DFT); the catalyst consists of transition metal M and heteroatom N4 co-doped in vacancy fullerene (M–N4–C64, M = Fe, Co, and Ni).

scholarly journals Density functional theory studies on the dissociation energies of metallic salts: Relationship between lattice and dissociation energies

2002 ◽  
Vol 23 (5) ◽  
pp. 584-584 ◽  
Author(s):  
Chang Kon Kim ◽  
Hongok Won ◽  
Hoon Sik Kim ◽  
Yong Soo Kang ◽  
Hong Guang Li ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Functional Theory ◽  
Dissociation Energies ◽  
Metallic Salts

A systematic computational investigations of water splitting and N2 reduction reaction performances of monolayer MBenes

2021 ◽  
Author(s):  
Yuwen Cheng ◽  
Jisheng Mo ◽  
Yongtao Li ◽  
Yan Song ◽  
Yumin Zhang
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
Water Splitting ◽  
Density Functional ◽  
Reduction Reaction ◽  
Functional Theory ◽  
Energy Conversion And Storage ◽  
Metal Borides ◽  
Potential Applications ◽  
And Storage

Recently, transition metal borides (MBenes, analogous to MXenes) have been attracted interest due to their potential applications in energy conversion and storage. In this work, we performed density functional theory...

CH2O Adsorption on M (M = Li, Mg and Al) Atom Deposited ZnO Nano-Cage: DFT Study

2018 ◽  
Vol 786 ◽  
pp. 384-392 ◽  
Author(s):  
Hussein Y. Ammar
Keyword(s):  
Density Functional Theory ◽  
Bond Length ◽  
Density Functional ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Structural And Electronic Properties ◽  
Formaldehyde Molecule ◽  
Electronic Configurations ◽  
Adsorption Energies ◽  
Homo Lumo

The structural and electronic properties of Li, Mg and Al deposited ZnO nanocages and their effects on the adsorption of formaldehyde molecule have been investigated using the density functional theory (DFT) computations. To understand the behavior of the adsorbed CH2O molecule on the ZnO nanocage, results of DFT calculations of the M-deposited nanocages (M=Li, Mg and Al), as well as complex systems consisting of the adsorbed CH2O molecule on M-deposited ZnO nanocage were reported. The results presented include adsorption energies, bond lengths, electronic configurations, density of states and molecular orbitals. It was found that, the most energetically stable adsorption configurations of CH2O molecule on the bare ZnO leads to 12% dilation in C=O bond length of CH2O and 14% decrease in HOMO-LUMO gap of ZnO cluster. The most energetically stable adsorption configurations of CH2O molecule on Li, Mg and Al-deposited ZnO lead to 4%, 4% and 11% dilation in C=O bond length of CH2O and-0.66, -45 and , +66% change in HOMO-LUMO gap of ZnO nanocages, respectively. The interaction between CH2O with bare ZnO and M-deposited ZnO nanocages is attributed to charge transfer mechanism. These results may be meaningful for CH2O degradation and detection.

scholarly journals A Free Aluminylene with Diverse σ-Donating and Doubly σ/π-Accepting Ligand Features for Transition Metals

2021 ◽  
Author(s):  
Xin Zhang ◽  
Liu Leo Liu
Keyword(s):  
Density Functional Theory ◽  
Coordination Chemistry ◽  
Transition Metals ◽  
Electronic Structures ◽  
Ligand Exchange ◽  
Density Functional ◽  
Reduction Reaction ◽  
Functional Theory ◽  
Metal Centers ◽  
Coordination Behavior

We report herein the synthesis, characterization, and coordination chemistry of a free N-aluminylene, namely a carbazolylaluminylene 2b. This species is prepared via a reduction reaction of the corresponding carbazolyl aluminium diiodide. The coordination behavior of 2b towards transition metal centers (W, Cr) is shown to afford a series of novel aluminylene complexes 3-6 with diverse coordination modes. We demonstrate that the Al center in 2b can behave as: 1. a σ-donating and doubly π-accepting ligand; 2. a σ-donating, σ-accepting and π-accepting ligand; and 3. a σ-donating and doubly σ-accepting ligand. Additionally, we show ligand exchange at the aluminylene center providing access to the modulation of electronic properties of transition metals without changing the coordinated atoms. Investigations of 2b with IDippCuCl (IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) show an unprecedented aluminylene-alumanyl transformation leading to a rare terminal Cu-alumanyl complex 8. The electronic structures of such complexes and the mechanism of the aluminylene-alumanyl transformation are investigated through density functional theory (DFT) calculations.

Sign in / Sign up

Export Citation Format

Share Document