Effect of the weak intermolecular C-H···O=C hydrogen bonding, solvent polarity and concentration on the frequency of the C=O stretch mode of 2-thiophenecarboxaldehyde.

The vibrational frequency shift in the C=O stretch mode of 2-thiophenecarboxaldehyde (2TC) in the condensed phase is still not fully understood. In this paper, the vibrational spectra of 2TC were investigated using the FT-Raman, FT-IR and resonance Raman spectroscopies in conjunction with the density functional theory calculation. The pure compound (in the neat liquid) exhibits three vibrational bands 1658, 1672 and 1687 cm in the ν spectral region.

Surface Surgery of the Nickel-Rich Cathode Material LiNiCoAlO: Toward a Complete and Ordered Surface Layered Structure and Better Electrochemical Properties.

A complete and ordered layered structure on the surface of LiNiCoAlO (NCA) has been achieved via a facile surface-oxidation method with NaSO. The field-emission transmission electron microscopy images clearly show that preoxidation of the hydroxide precursor can eliminate the crystal defects and convert Ni(OH) into layered β-NiOOH, which leads to a highly ordered crystalline NCA, with its (006) planes perpendicular to the surface in the sintering process. X-ray photoelectron spectroscopy and Raman shift results demonstrate that the contents of Ni and Co ions are reduced with preoxidization on the surface of the hydroxide precursor.