Analysis of Lithium Insertion/Desorption Reaction at Interfaces between Graphite Electrodes and Electrolyte Solution Using Density Functional + Implicit Solvation Theory

Correction for ‘Fragment density functional theory calculation of NMR chemical shifts for proteins with implicit solvation’ by Tong Zhu et al., Phys. Chem. Chem. Phys., 2012, 14, 7837–7845.

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The Role of Oxygenic Groups and Sp3 Carbon Hybridization in Activated Graphite Electrodes for Vanadium Redox Flow Batteries

10.26434/chemrxiv.14546847 ◽

2021 ◽

Author(s):

Ali Hassan ◽

Asnake Sahele Haile ◽

Theodore Tzedakis ◽

Heine Anton Hansen ◽

Piotr de Silva

Keyword(s):

Dft Calculations ◽

Density Functional ◽

Vanadium Redox Flow Battery ◽

Carbon Surface ◽

Graphite Electrodes ◽

Functional Theory ◽

Redox Flow Batteries ◽

Flow Batteries ◽

Vanadium Redox

Graphite felt is a widely used electrode material for vanadium redox flow batteries. Electrode activation leads to the functionalization of the graphite surface with epoxy, OH, C=O, and COOH oxygenic groups and changes the carbon surface morphology and electronic structure; thus, improving the electrode’s electroactivity relative to the untreated graphite. In this study, we conduct density functional theory (DFT) calculations to evaluate functionalization’s role towards the positive half-cell reaction of the vanadium redox flow battery. The DFT calculations show that oxygenic groups improve the graphite felt’s affinity towards the VO2+/VO2+ redox couple in the following order: C=O > COOH > OH > basal plane. Projected density of states (PDOS) calculations show that these groups increase the electrode’s sp3 hybridization in the same order. We conclude that the increase in the sp3 hybridization is responsible for the improved electroactivity, while the oxygenic groups’ presence is responsible for this sp3 increment. These insights can help in the better selection of activation processes and optimization of their parameters.

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Comparison of computational chemistry methods for the discovery of quinone-based electroactive compounds for energy storage

Scientific Reports ◽

10.1038/s41598-020-79153-w ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Qi Zhang ◽

Abhishek Khetan ◽

Süleyman Er

Keyword(s):

Energy Storage ◽

Prediction Accuracy ◽

Density Functional ◽

Single Point ◽

Computational Cost ◽

Systematic Evaluation ◽

Redox Potentials ◽

Implicit Solvation ◽

Point Energy ◽

Computational Screening

AbstractHigh-throughput computational screening (HTCS) is a powerful approach for the rational and time-efficient design of electroactive compounds. The effectiveness of HTCS is dependent on accuracy and speed at which the performance descriptors can be estimated for possibly millions of candidate compounds. Here, a systematic evaluation of computational methods, including force field (FF), semi-empirical quantum mechanics (SEQM), density functional based tight binding (DFTB), and density functional theory (DFT), is performed on the basis of their accuracy in predicting the redox potentials of redox-active organic compounds. Geometry optimizations at low-level theories followed by single point energy (SPE) DFT calculations that include an implicit solvation model are found to offer equipollent accuracy as the high-level DFT methods, albeit at significantly lower computational costs. Effects of implicit solvation on molecular geometries and SPEs, and their overall effects on the prediction accuracy of redox potentials are analyzed in view of computational cost versus prediction accuracy, which outlines the best choice of methods corresponding to a desired level of accuracy. The modular computational approach is applicable for accelerating the virtual studies on functional quinones and the respective discovery of candidate compounds for energy storage.

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B-DNA model systems in non-terran bio-solvents: implications for structure, stability and replication

Physical Chemistry Chemical Physics ◽

10.1039/c7cp01908d ◽

2017 ◽

Vol 19 (26) ◽

pp. 16969-16978 ◽

Cited By ~ 12

Author(s):

Trevor A. Hamlin ◽

Jordi Poater ◽

Célia Fonseca Guerra ◽

F. Matthias Bickelhaupt

Keyword(s):

Density Functional Theory ◽

Gas Phase ◽

Density Functional ◽

Model Systems ◽

Structure Stability ◽

Implicit Solvation ◽

Base Pairs ◽

Functional Theory ◽

Dna Base ◽

Dna Base Pairs

We have computationally analyzed a comprehensive series of Watson–Crick and mismatched B-DNA base pairs, in the gas phase and in several solvents, including toluene, chloroform, ammonia, methanol and water, using dispersion-corrected density functional theory and implicit solvation.

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Self-Consistent Density Functional Approach to a Metal/Electrolyte Solution Interface

Zeitschrift für Naturforschung A ◽

10.1515/zna-1984-1119 ◽

1984 ◽

Vol 39 (11) ◽

pp. 1122-1133 ◽

Cited By ~ 2

Author(s):

A. A. Kornyshev ◽

M. B. Partenskii ◽

W. Schmickler

Keyword(s):

Electrolyte Solution ◽

Free Electron ◽

Density Functional ◽

Functional Approach ◽

Electron Cloud ◽

System Parameters ◽

Solution Interface ◽

Self Consistent ◽

Concentrated Solution ◽

Solvent Molecules

Two models for a plane interface between a free electron metal and a concentrated solution of a surface inactive electrolyte are treated fully self-consistently, taking into account both the polarizability of the metallic electron cloud and the reorientation of solvent molecules. The interfacial capacity is calculated as a function of the electrode charge, and its dependence on various system parameters is investigated. Some conclusions on the structure of the interface are drawn from a comparison between our results and experimentally observed trends.

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Fragment density functional theory calculation of NMR chemical shifts for proteins with implicit solvation

Physical Chemistry Chemical Physics ◽

10.1039/c2cp23746f ◽

2012 ◽

Vol 14 (21) ◽

pp. 7837-7845 ◽

Cited By ~ 64

Author(s):

Tong Zhu ◽

Xiao He ◽

John Z. H. Zhang

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Chemical Shifts ◽

Density Functional Theory Calculation ◽

Implicit Solvation ◽

Functional Theory ◽

Nmr Chemical Shifts ◽

Theory Calculation

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Comparison of Computational Chemistry Methods for the Discovery of Quinone-Based Electroactive Compounds for Energy Storage

10.26434/chemrxiv.12893825 ◽

2020 ◽

Author(s):

Qi Zhang ◽

Abhishek Khetan ◽

Süleyman Er

Keyword(s):

Energy Storage ◽

Prediction Accuracy ◽

Density Functional ◽

Single Point ◽

Computational Cost ◽

Systematic Evaluation ◽

Redox Potentials ◽

Implicit Solvation ◽

Point Energy ◽

Computational Screening

High-throughput computational screening (HTCS) is an approach that can enable rational and time-efficient discovery of electroactive compounds. The effectiveness of HTCS is dependent on the accuracy and speed at which the performance descriptors can be estimated for possibly millions of candidate compounds. Here, a systematic evaluation of computational methods, including force field (FF), semi-empirical quantum mechanics (SEQM), density functional based tight binding (DFTB), and density functional theory (DFT), is performed on the basis of their accuracy in predicting the redox potentials of redox-active organic compounds. Geometry optimizations at lower level theories followed by single point energy (SPE) DFT calculations including an implicit solvation model are found to offer equipollent accuracy as the higher level DFT methods, albeit at significantly lower computational costs. Effects of implicit solvation on molecular geometries and SPEs, and their overall effects on the prediction accuracy of redox potentials are analyzed in view of computational cost versus prediction accuracy, which outlines the best choice of methods corresponding to a desired level of accuracy. The modular computational approach presented here is expected to be applicable for accelerating virtual studies on functional quinones and the respective discovery of candidate compounds for energy storage.

Download Full-text