Figure 2.

Spectroscopic characterization of the NCs before and after LiPF₆ etching and HRTEM analysis (including carbon coating). (a) Liquid-phase ¹H NMR spectra of a solution of LiFePO₄ NCs before (black line) and after LiPF₆ treatment (orange line, 10× magnified); (b) FTIR spectra of NC films on silicon substrates: as synthesized NCs, coated with Olam (black line); etched NCs (red line); (c) HRTEM images of: (left) as-synthesized NCs; (center) LiPF₆ etched NCs; (right) LiPF₆ etched NCs after carbon coating. (d) Scheme depicting how etching of the LiFePO₄ NC surface can lead to an intimate contact between the surface and the carbon layer during the carbon coating step.