Fig. 3: Surface enrichment of La on the LNMO samples.
From: Epitaxial growth of an atom-thin layer on a LiNi0.5Mn1.5O4 cathode for stable Li-ion battery cycling
a Integrated normalized intensities of LaTMO3 peaks as a function of relative La concentration, normalized on the LNMO (311) peak. The fitting errors (R2) are 0.9953 and 0.9655 for ~200 and ~900 nm LNMO crystals. b Surface to volume ratio as a function of the size of the LNMO octahedra. The surface adsorption fraction depends on the size of the LNMO octahedra shows a shift to higher values for smaller crystals (inset shows the SEM images). Coloured lines indicate the points on this curve as extracted from the data in (a). c NEXAFS spectra of La and Ni signals showing increasing surface presence of La for La doping precursor, LNMO-D0.5La, and LNMO-C0.5La (the integrated intensity is normalized to the Ni peak). d XPS spectra of LNMO-C0.5La etched by Ar+ etching as a function of etching time. e HAADF-STEM image of a typical BLNMO-C1.0La. f Corresponding elemental mappings of (e).
