Wu T, Qi J, Xu M, Zhou D, Xiao Z. Selective S/Li
2S Conversion
via in-Built Crystal Facet Self-Mediation: Toward High Volumetric Energy Density Lithium-Sulfur Batteries.
ACS NANO 2020;
14:15011-15022. [PMID:
33112596 DOI:
10.1021/acsnano.0c04933]
[Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The gravimetric, areal, and volumetric capacities pose important influences on market penetration for secondary batteries. Carbonaceous materials take a leading stand for the improvement of gravimetric and areal capacity in lithium-sulfur batteries; however, they exhibit some intrinsic deficiencies, including insufficient fixation on lithium polysulfides (LiPS) and low tap density, incurring poor volumetric performance and inferior cycling behavior. Here, we report a sulfur cathode based on highly conductive ZrB2 nanoflakes with only 2 wt % conductive carbon. The resultant closely packed ZrB2-S electrode delivers a high areal capacity of 8.5 mAh cm-2 and cell-level volumetric energy density of 533 Wh L-1 with a high sulfur loading of 7.8 mg cm-2 and an ultralow electrolyte dosage. With combined spectroscopic studies and theoretical calculation results, it was confirmed that an in-built Janus crystal facet self-mediation is on-site constructed by the exposed B and Zr atoms for an effective bonding and selective conversion on LiPS upon charge-discharge processes.
Collapse