High-voltage lithium metal batteries (LMBs) are a promising high-energy density energy storage system. However, their practical implementations are impeded by short lifespan due to uncontrolled lithium dendrite growth, narrow electrochemical stability window, and safety concerns of liquid electrolytes. Here, a porous composite aerogel is reported as the gel electrolyte (GE) matrix, made of metal–organic framework (MOF)@bacterial cellulose (BC), to enable long-life LMBs under high voltage. The effectiveness of suppressing dendrite growth is achieved by regulating ion deposition and facilitating ion conduction. Specifically, two hierarchical mesoporous Zr-based MOFs with different organic linkers, that is, UiO-66 and NH2-UiO-66, are embedded into BC aerogel skeletons. The results indicate that NH2-UiO-66 with anionphilic linkers is more effective in increasing the Li+ transference number; the intermolecular interactions between BC and NH2-UiO-66 markedly increase the electrochemical stability. The resulting GE shows high ionic conductivity (≈1 mS cm−1), high Li+ transference number (0.82), wide electrochemical stability window (4.9 V), and excellent thermal stability. Incorporating this GE in a symmetrical Li cell successfully prolongs the cycle life to 1200 h. Paired with the Ni-rich LiNiCoAlO2 (Ni: Co: Al = 8.15:1.5:0.35, NCA) cathode, the NH2-UiO-66@BC GE significantly improves the capacity, rate performance, and cycle stability, manifesting its feasibility to operate under high voltage.
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Ionic Liquid Welding of the UIO-66-NH2 MOF to Cotton Textiles
Ionic liquid based fiber welding has been used to attach the metal−organic framework (MOF) UiO-66-NH2to cotton fibers. The results show that by controlling the extent of the welding process, it is possible to produce fibers that contain a high surface area (approximately 50−100 m2/ g), an X-ray diffraction pattern consistent with UiO-66-NH2, and fibers that are chemically reactive to dimethyl 4-nitrophenyl phosphate (DMNP), a common chemical weapon simulant. The ionic liquid/MOF welding solution can be applied by directly placing the fabric in the welding solution or by utilizing an airbrushing technique. Both welding techniques are shown to be scalable with results collected on approximately 1×1, 5 ×5, and 15.5×15.5 in. swatches. The results are also applicable to weaving methods where the MOF is welded to individual threads and subsequently woven into a textile. The results provide an industrially scalable method of attaching a wide variety of MOFs to cotton textiles, which does not require synthesizing the MOF in the presence of the textile.
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- Award ID(s):
- 1726263
- PAR ID:
- 10207558
- Date Published:
- Journal Name:
- Industrial engineering chemistry research
- Volume:
- 59
- Issue:
- 43
- ISSN:
- 1520-5045
- Page Range / eLocation ID:
- 19285-19298
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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