Abstract
In an age of rapid acceleration toward next-generation energy storage technologies, lithium-sulfur (Li-S) batteries offer the desirable combination of low weight and high specific energy. Metal-organic frameworks (MOFs) have been recently studied as functionalizable platforms to improve Li-S battery performance. However, many MOF-enabled Li-S technologies are hindered by low capacity retention and poor long-term performance due to low electronic conductivity. In this work, we combine the advantages of a Zr-based MOF-808 loaded with sulfur as the active material with a graphene/ethyl cellulose additive, leading to a high-density nanocomposite electrode requiring minimal carbon. Our electrochemical results indicate that the nanocomposites deliver enhanced specific capacity over conventionally used carbon/binder mixtures, and postsynthetic modification of the MOF with lithium thiophosphate results in further improvement. Furthermore, the dense form factor of the sulfur-loaded MOF-graphene nanocomposite electrodes provides high volumetric capacity compared to other works with significantly more carbon additives. Overall, we have demonstrated a proof-of-concept paradigm where graphene nanosheets facilitate improved charge transport because of enhanced interfacial contact with the active material. This materials engineering approach can likely be extended to other MOF systems, contributing to an emerging class of two-dimensional nanomaterial-enabled Li-S batteries.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 37173-37181 |
| Number of pages | 9 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 12 |
| Issue number | 33 |
| DOIs | |
| State | Published - Aug 19 2020 |
Funding
A.E.B., D.A.B., and V.S.T. thank the National Science Foundation CAREER Award (DMR-1945114) and the Department of Chemistry and Johns Hopkins University (JHU) for instrumentation support, graduate student support, and start-up funding. A.E.B. and D.A.B. also received the Harry and Cleio Greer Fellowships from the JHU Department of Chemistry. A.E.B. acknowledges support from the ARCS Foundation for the Metropolitan Washington Chapter Scholar Award. J.R.D. and M.C.H. thank the National Science Foundation Scalable Nanomanufacturing Program (NSF CMMI-1727846). J.R.D. also acknowledges the National Consortium for Graduate Degrees for Minorities in Engineering and Science Fellowship sponsored by the 3M Company and Northwestern University. This work made use of the EPIC facility and Keck-II facilities of Northwestern University’s NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR-1720139) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. The MatCI facility at Northwestern University was also used, which is supported by the MRSEC program (NSF DMR-1720139). We also acknowledge Hector Vivanco and Prof. Tyrel McQueen (Dept. of Chemistry, JHU) for XRD instrumentation support, as well as Ethan Secor for initial graphene ink development and consultation, Chen “Leo” Ling for data analysis support, and Jin-Myoung Lim for helpful discussions (Dept. of Materials Science and Engineering, NU).
Keywords
- Energy storage
- Graphene
- High packing density
- Lithium-sulfur battery
- Metal-organic framework
- Nanocomposite
- Thiophosphate
- Volumetric capacity
ASJC Scopus subject areas
- General Materials Science
