skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Thermally fabricated cobalt telluride in nitrogen-rich carbon dodecahedra as high-rate potassium and sodium ion battery anodes
Title: Thermally fabricated cobalt telluride in nitrogen-rich carbon dodecahedra as high-rate potassium and sodium ion battery anodes
Cobalt telluride anchored to nitrogen-rich carbon dodecahedra (CoTe@NCD) was synthesized by simultaneous pyrolysis-tellurium melt impregnation of ZIF-67 MOFs. The purely thermal method involved no secondary chemicals and no waste byproducts. The result is a microstructure consisting of nanoscale 86 wt% CoTe intermetallic nanoparticles contained within a thin N-rich carbon matrix. During electrochemical cycling, the 21 nm average diameter CoTe provides short diffusion paths for Na + /K + ions, which in conjunction with the electrically conducting carbon matrix allow for rapid potassiation or sodiation. As potassium ion battery (PIB and KIB) and sodium ion battery (NIB and SIB) anodes, CoTe@NCD demonstrates attractive reversible capacity, promising cycling stability, and state-of-the-art rate performance. For example, as a KIB anode, the CoTe@NCD electrode exhibits a reversible capacity of 380 mA h g −1 at 50 mA g −1 and a fast charge capacity of 136 mA h g −1 at 1000 mA g −1 . As a NIB anode, it also displays excellent rate capability achieving 620 mA h g −1 at 50 mA g −1 and 345 mA h g −1 at 1000 mA g −1 .  more » « less
Award ID(s):
1911905
PAR ID:
10354201
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Sustainable Energy & Fuels
Volume:
6
Issue:
15
ISSN:
2398-4902
Page Range / eLocation ID:
3582 to 3590
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; (, Energy & Environmental Science)
    null (Ed.)
    Both electronic and ionic conductivities are of high importance to the performance of anode materials for Li-ion batteries. Many large capacity anode materials (such as Ge) do not have sufficiently high electronic and ionic conductivities required for high-rate cycling. Here, we report a novel ternary compound, copper germanium phosphide (CuGe 2 P 3 ), as a high-rate anode. Being synthesized via a facile and scalable mechanochemistry method, CuGe 2 P 3 has a cation-disordered sphalerite structure and offers higher ionic and electronic conductivities and better tolerance to volume change during cycling than Ge, as confirmed by first principles calculations and experimental characterization, including high-resolution synchrotron X-ray diffraction, HRTEM, SAED, XPS and Raman spectroscopy. Furthermore, the results suggest that CuGe 2 P 3 has a reversible Li-storage mechanism of conversion reaction. When composited with graphite by virtue of a two-stage ball-milling process, the yolk–shell structure of the amorphous carbon-coated CuGe 2 P 3 nanocomposite (CuGe 2 P 3 /C@Graphene) delivers a high initial coulombic efficiency (91%), a superior cycling stability (1312 mA h g −1 capacity after 600 cycles at 0.2 A g −1 and 876 mA h g −1 capacity after 1600 cycles at 2 A g −1 ), and an excellent rate capability (386 mA h g −1 capacity at 30 A g −1 ), surpassing most Ge-based anodes reported to date. Moreover, a series of cation-disordered new phases in the Cu(Zn)–Ge–P family with various cation ratios offer similar Li-storage properties, achieving high reversible capacities with high initial coulombic efficiencies and desirable redox chemistry with improved safety. 
    more » « less
  2. ; ; ; ; ; ; (, Fuel Processing Technology)
    This work explores a novel approach for improving the sodium-ion battery performance of coal char using flash pyrolysis and an ether-based electrolyte. Coal char is an ultra-low cost hard carbon with promising application as an anode material in sodium-ion batteries. During flash pyrolysis, char is heated at 1000 °C/s in a drop-tube furnace to create a highly-irregular structure. The larger d-spacing and smaller closed micropore diameter of flash-pyrolyzed char increases anode capacity compared to traditional slow-pyrolyzed char electrodes. The sodium-ion battery anode performance of flash-pyrolyzed char is further improved using an ether-based electrolyte in place of the traditional ester-based electrolyte. Performance improvements include greater initial Coulombic efficiency (58% in ester- vs. 64% in ether-based electrolyte) and improved specific capacity in an ether-based electrolyte. Overall, the combination of flash pyrolysis and ether-based electrolyte increases the sodium-ion battery discharge capacity of coal char by over 50%, from 72.5 mAh g−1 (slow-pyrolyzed char in ester-based electrolyte) to 109.4 mAh g−1 (flash-pyrolyzed char in ether-based electrolyte) (50 mA g−1 discharge rate). The results highlight improvements that can be realized through flash pyrolysis of coal char for battery applications and the numerous processing advantages of flash vs. slow pyrolysis. 
    more » « less
  3. ; ; ; ; ; ; ; (, Energy & Environmental Science)
    null (Ed.)
    Sodium metal battery (SMB, NMB) anodes can become dendritic due to an electrochemically unstable native Na-based solid electrolyte interphase (SEI). Herein Li-ion activated tin sulfide graphene nanocomposite membrane (A-SnS–G) is employed as an artificial SEI layer, allowing cyclability of record-thin 100 μm Na metal foils. The thin Na metal is prepared by a self-designed metallurgical rolling protocol. A-SnS–G is initially placed onto the polypropylene (PP) separator but becomes in situ transferred onto the Na metal surface. Symmetric metal cells protected by A-SnS–G achieve low-overpotential extended high-rate cycling in a standard carbonate electrolyte (EC : DEC = 1 : 1, 5% FEC). Accumulated capacity of 1000 mA h cm −2 is obtained after 500 cycles at 4 mA cm −2 , with accumulated capacity-to-foil capacity (A/F) ratio of 90.9. This is among the most favorable cycle life, accumulated capacity, and anode utilization combinations reported. Protection by non-activated SnS–G membrane yields significantly worse cycling, albeit still superior to the baseline unprotected sodium. Post-mortem and dedicated light optical analysis indicate that metal swelling, dendrite growth and dead metal formation is extensive for the unprotected sample, but is suppressed with A-SnS–G. Per XPS, post-100 cycles near-surface structure of A-SnS–G is rich in metallic Sn alloys and inorganic carbonate salts. Even after 300 cycles, Li-based SEI components ROCO 2 -Li, Li 2 CO 3 and LiF are detected with A-SnS–G. As a proof of principle, an SMB with a high mass loading (6 mg cm −2 ) NVP cathode and a A-SnS–G protected anode delivered extended cyclability, achieving 74 mA h g −1 after 400 cycles at 0.4C. 
    more » « less
  4. ; ; ; ; (, ECS Advances)
    Deriving battery grade materials from natural sources is a key element to establishing sustainable energy storage technologies. In this work, we present the use of avocado peels as a sustainable source for conversion into hard carbon-based anodes for sodium ion batteries. The avocado peels are simply washed and dried then proceeded to a high temperature conversion step. Materials characterization reveals conversion of the avocado peels in high purity, highly porous hard carbon powders. When prepared as anode materials they show to the capability to reversibly store and release sodium ions. The hard carbon-based electrodes exhibit excellent cycling performance, namely, a reversible capacity of 352.55 mAh g−1at 0.05 A g−1, rate capability up to 86 mAh g−1at 3500 mA g−1, capacity retention of >90%, and 99.9% coulombic efficiencies after 500 cycles. Cyclic voltammetry studies indicated that the storage process was diffusion-limited, with diffusion coefficient of 8.62 × 10−8cm2s−1. This study demonstrates avocado derived hard carbon as a sustainable source that can provide excellent electrochemical and battery performance as anodes in sodium ion batteries. 
    more » « less
  5. ; ; ; ; (, MRS Advances)
    ABSTRACT This study reports a high-performance tin (Sn)-coated vertically aligned carbon nanofiber array anode for lithium-ion batteries. The array electrodes have been prepared by coaxial sputter-coating of tin (Sn) shells on vertically aligned carbon nanofiber (VACNF) cores. The robust brush-like highly conductive VACNFs effectively connect high-capacity Sn shells for lithium-ion storage. A high specific capacity of 815 mAh g -1 of Sn was obtained at C/20 rate, reaching toward the maximum value of Sn. However, the electrode shows poor cycling performance with conventional LiPF 6 based organic electrolyte. The addition of fluoroethylene carbonate (FEC) improve the performance significantly and the Sn-coated VACNFs anode shows stable cycling performance. The Sn-coated VACNF array anodes exhibit outstanding capacity retention in the half-cell tests with electrolyte containing 10 wt.% FEC and could deliver a reversible capacity of 480 mAh g -1 after 50 cycles at C/3 rate. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email