Title: Improving Electronic Conductivity of Layered Oxides through the Formation of Two-Dimensional Heterointerface for Intercalation Batteries

Abstract

Synthetic strategies for the improvement in electronic conductivities and electrochemical stabilities of transition metal oxide cathodes, which are limiting factors in the performance of commercial intercalation batteries, are required for next-generation, high-performance battery systems. Furthermore, the chemical preintercalation approach, consisting of a combined sequence of a sol–gel process, extended aging, and a hydrothermal treatment, is a versatile, wet synthesis technique that allows for the incorporation of a polar species between the layers of transition metal oxides. Here, formation of a layered 2D δ-C_xV₂O₅·nH₂O heterostructure occurs via chemical preintercalation of dopamine molecules between bilayers of vanadium oxide followed by the hydrothermal treatment of the precipitate, leading to carbonization of the organic molecules. The presence of carbon layers within the structure has been confirmed via a combined analysis of scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, Raman spectroscopy, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, four-probe conductivity measurements, and scanning transmission electron microscopy characterization. 2D δ-C_xV₂O₅·nH₂O heterostructure electrodes demonstrated significantly improved electrochemical performance, particularly at higher current densities, in Li-ion cells. The heterostructure electrodes exhibited 75% of the capacity retention when the current was changed from 20 mA g^–1 (206 mAh g^–1) to 300 mA g^–1 (155 mAh g^–1), while the reference δ-V₂O₅·nH₂Omore » electrodes exhibited only 10% capacity retention in the same experiment. Remarkably, 2D δ-C_xV₂O₅·nH₂O heterostructure electrodes demonstrated significantly improved capacity retention (94% after 30 cycles) for bilayered vanadium oxide electrodes in Li-ion cells during galvanostatic cycling at 20 mA g^–1. The improved electrochemical performance, in both extended cycling and rate capability studies, of the 2D δ-C_xV₂O₅·nH₂O heterostructure electrodes in the Li-ion system is ascribed to the intermittent formation of carbon layers within the bilayered structure, which leads to increased electronic conductivity and improved structural stability of the heterostructure compared to the reference δ-V₂O₅·nH₂O electrodes.« less

Authors:

Clites, Mallory ^[1]; Andris, Ryan ^[2]; Cullen, David A.  ^[3];

• Search DOE PAGES for author "Cullen, David A."
• Search DOE PAGES for ORCID "0000-0002-2593-7866"

More, Karren L.  ^[3];

• Search DOE PAGES for author "More, Karren L."
• Search DOE PAGES for ORCID "0000-0001-5223-9097"

Pomerantseva, Ekaterina  ^[1]

• Search DOE PAGES for author "Pomerantseva, Ekaterina"
• Search DOE PAGES for ORCID "0000-0002-6765-7133"

---

+ Show Author Affiliations

1. Drexel Univ., Philadelphia, PA (United States)
2. Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104, United States
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)

Publication Date:

Tue Mar 24 00:00:00 EDT 2020

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1712725

Grant/Contract Number:  

AC05-00OR22725; DMR-1752623

Resource Type:

Accepted Manuscript

Journal Name:

ACS Applied Energy Materials

Additional Journal Information:

Journal Volume: 3; Journal Issue: 4; Journal ID: ISSN 2574-0962

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

25 ENERGY STORAGE; chemical preintercalation synthesis approach; bilayered vanadium oxide; two-dimensional heterostructures; carbonization; Li-ion and Na-ion batteries