Exploring the sodium storage mechanism in disodium terephthalate as anode for organic battery using density-functional theory calculations

Exploring the sodium storage mechanism in disodium terephthalate as anode for organic battery... We present an ab initio study of sodium storage mechanism in disodium terephthalate (Na2TP) which is a very promising anode material for organic sodium (Na)-ion batteries with reported experimental capacities of ∼255 mAh g−1, previously attributed to Na attachment to the two carboxylate groups (coordinating to oxygen atoms). We show here that the inserted Na atoms prefer to bind at carboxylate sites at low Na concentrations and are dominant for insertion of up to one Na atom per molecule; for higher Na concentrations, the hexagonal sites (on the aromatic ring) become dominant. We confirm that the Na2TP crystal can store a maximum of two Na atoms per molecule, as observed in experiments. Our current results are intriguing as we reveal that the Na binding at carboxylate sites contributes to the initial part of Na2TP sodiation curve and the Na binding at hexagonal sites contributes to the second part of the curve. The inserted Na atoms donate electrons to empty states in the conduction band. Moreover, we show that the Na diffusion barriers in clean Na2TP can be as low as 0.23 eV. We also show that there is significant difference in the mechanism of Na interaction between individual molecules and the crystal. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Power Sources Elsevier

Exploring the sodium storage mechanism in disodium terephthalate as anode for organic battery using density-functional theory calculations

Loading next page...
 
/lp/elsevier/exploring-the-sodium-storage-mechanism-in-disodium-terephthalate-as-cDvkT9Jrx9
Publisher
Elsevier
Copyright
Copyright © 2016 Elsevier B.V.
ISSN
0378-7753
D.O.I.
10.1016/j.jpowsour.2016.05.101
Publisher site
See Article on Publisher Site

Abstract

We present an ab initio study of sodium storage mechanism in disodium terephthalate (Na2TP) which is a very promising anode material for organic sodium (Na)-ion batteries with reported experimental capacities of ∼255 mAh g−1, previously attributed to Na attachment to the two carboxylate groups (coordinating to oxygen atoms). We show here that the inserted Na atoms prefer to bind at carboxylate sites at low Na concentrations and are dominant for insertion of up to one Na atom per molecule; for higher Na concentrations, the hexagonal sites (on the aromatic ring) become dominant. We confirm that the Na2TP crystal can store a maximum of two Na atoms per molecule, as observed in experiments. Our current results are intriguing as we reveal that the Na binding at carboxylate sites contributes to the initial part of Na2TP sodiation curve and the Na binding at hexagonal sites contributes to the second part of the curve. The inserted Na atoms donate electrons to empty states in the conduction band. Moreover, we show that the Na diffusion barriers in clean Na2TP can be as low as 0.23 eV. We also show that there is significant difference in the mechanism of Na interaction between individual molecules and the crystal.

Journal

Journal of Power SourcesElsevier

Published: Aug 30, 2016

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve Freelancer

DeepDyve Pro

Price
FREE
$49/month

$360/year
Save searches from
Google Scholar,
PubMed
Create lists to
organize your research
Export lists, citations
Read DeepDyve articles
Abstract access only
Unlimited access to over
18 million full-text articles
Print
20 pages/month
PDF Discount
20% off