Variation of the composition and properties of lithium manganese oxide spinel in lithiation-delithiation cycles

Aerosol Cross-Linked Crown Ether Diols Melded with Poly(vinyl alcohol) as Specialized Microfibrous Li+ Adsorbents

“…FTIR spectra of MFs were recorded on a VARIAN 2000 (Scimitar Series) using the standard attenuated total reflection method. The solid-state (SS) 13 C NMR spectra with cross-polarization magic angle spinning ( 13 C CP-MAS NMR, Zr rotor Ø out = 4 mm, 12 kHz spinning rate) were acquired on a 400 MHz SS-NMR (9.4 T) spectrometer (AVANCE III HD, Bruker, Germany). The MFs were examined under a field emission scanning electron microscope (FE-SEM, II-EDS-EBSD, JEOL JSM-7000F, Japan).…”

“…The reactions were easy to perform 22 and afforded moderate to high yields (65− 85%) as confirmed by 1 H and 13…”

“…Other familiar peaks were also present like the doublets of C−H stretching (2919−2912 and 2873−2860 cm −1 ) from the alkyl components of GA and CEs. 34,50 Because evidence of CE−GA−PVA cross-linking is difficult to observe in FTIR alone, 13 C CP-MAS NMR analysis was also carried out. The 13 C CP-MAS NMR spectra provided some insights (details in p S-25, SI) into the nature of the cross-links formed.…”

“…Hemiacetal carbons between CE/GA and PVA/GA linkages were also detected (IV). 57 Detailed discussion on 13 C CP-MAS NMR results can be found in p S-25−S-31, SI and Figure S20, SI.…”

“…Depending on their preparation, LIS capacities in diluted Li + sources vary from 0.7 to 41 mg Li + g –1 . However, LIS exhibit slow internal Li + diffusion due to their dense lattice structures. ,− They are moderately stable in acidic environment, and their fabrications require energy-intensive solid-state (SS) reactions. − These limitations motivated further research on other Li + adsorbents.…”