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Abstract Lithium/fluorinated graphite (Li/CFx) primary batteries show great promise for applications in a wide range of energy storage systems due to their high energy density (>2100 Wh kg–1) and low self‐discharge rate (<0.5% per year at 25 °C). While the electrochemical performance of the CFxcathode is indeed promising, the discharge reaction mechanism is not thoroughly understood to date. In this article, a multiscale investigation of the CFxdischarge mechanism is performed using a novel cathode structure to minimize the carbon and fluorine additives for precise cathode characterizations. Titration gas chromatography, X‐ray diffraction, Raman spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, cross‐sectional focused ion beam, high‐resolution transmission electron microscopy, and scanning transmission electron microscopy with electron energy loss spectroscopy are utilized to investigate this system. Results show no metallic lithium deposition or intercalation during the discharge reaction. Crystalline lithium fluoride particles uniformly distributed with <10 nm sizes into the CFxlayers, and carbon with lower sp2content similar to the hard‐carbon structure are the products during discharge. This work deepens the understanding of CFxas a high energy density cathode material and highlights the need for future investigations on primary battery materials to advance performance.
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Ultrasmall Cu I Nanoparticles Stabilized on Surface of HPMC: An Efficient Catalyst for Fast and Organic Solvent‐Free Tandem Click Chemistry in Water
Abstract A simple and environmentally benign technology for synthesizing ultrasmall CuInanoparticles (NPs) on the surface of the food additive hydroxypropyl methylcellulose (HPMC) and their application in completely organic solvent‐free tandem alkyne‐azide cycloaddition reactions were reported. The NP catalyst was thoroughly characterized by high‐angle annular dark‐field scanning transmission electron microscopy, high‐resolution transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy analysis for its morphology, particle size distribution, chemical composition, and oxidation state analyses. The NP catalyst was highly efficient, affording products in 10–45 min. All products were obtained in high purity by simple filtration, obviating organic solvents from the reaction set‐up to product isolation. The methodology is general and scalable as validated by a broad substrate scope.
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- Award ID(s):
- 2044778
- PAR ID:
- 10386464
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSusChem
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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