Porous carbon has been applied for lithium-sulfur battery cathodes, and carbonized metal–organic framework (MOF) is advantageous in tuning the morphology. Herein, we have systematically synthesized water-distorted MOF (WDM) derived porous carbon via controlling the proportion of both water in a mixed solvent (dimethylformamide and water) and ligand in MOF-5 precursors (metal and ligand), which is categorized by its morphology (i.e. Cracked stone (closed), Tassel (open) and Intermediate (semi-open)). For example, decrease in water and increase in ligand content induce Cracked stone WDMs which showed the highest specific surface area (2742–2990 m2/g) and pore volume (2.81–3.28 cm3/g) after carbonization. Morphological effect of carbonized WDMs (CWDMs) on battery performance was examined by introducing electrolytes with different sulfur reduction mechanisms (i.e. DOL/DME and ACN2LiTFSI-TTE): Closed framework effectively confines polysulfide, whereas open framework enhances electrolyte accessibility. The initial capacities of the batteries were in the following order: Cracked stone > Intermediate > Tassel for DOL/DME and Intermediate > Tassel > Cracked stone for ACN2LiTFSI-TTE. To note, Intermediate CWDM exhibited the highest initial capacity and retained capacity after 100 cycles (1398 and 747 mAh/g) in ACN2LiTFSI-TTE electrolyte having advantages from both open and closed frameworks. In sum, we could correlate cathode morphology (openness and pore structure) and electrolyte type (i.e. polysulfide solubility) with lithium-sulfur battery performance.
|Number of pages||13|
|Journal||Journal of Energy Chemistry|
|Publication status||Published - 2021 Oct|
Bibliographical noteFunding Information:
This work was supported by the Basic Science Research Program through the National Research Foundation of Korea by the Korea government (MEST) (grant number NRF-2019R1A2C4069922); and the “LG Research Fund for New Faculty” by LG Chem.
© 2021 Science Press
All Science Journal Classification (ASJC) codes
- Fuel Technology
- Energy Engineering and Power Technology
- Energy (miscellaneous)